>> pelley: tonight, late hoff breaking revelations in the colorado theater massacre. prosecutors say james holmes was barred from his university and made threats just weeks before the shooting. john miller has details. our new poll shows the president holding on to his lead in one key state, but his edge is shrinking? two others. reports from jan crawford and nancy cordes. there's an epidemic of murder in chicago, and a federal agent tells armen keteyian you of you can trace it to mexico. >> the most powerful drug lord in the world is operating out of this city. >> pelley: and one year after the east coast earthquake, sharyl attkisson is with an artist doing the work of the lord.

captioning sponsored by cbs this is the "cbs evening news" with scott pelley. >> pelley: good evening. we're learning tonight that before last month's theater massacre in colorado, officials at the university of colorado invalidated the access key of james holmes so he could no longer enter the buildings of the medical school campus. that was part of what prosecutors revealed in a court hearing today that was attended by holmes. the prosecutors are asking the judge for holmes' records and e-mails from his time as a student at the university where he was studying for a ph.d. in neuroscience. they're hoping to establish a motive in the shooting that lled 12 and wounded 58 others. senior correspondent john miller is joining us. and, john, what else did we learn? >> reporter: well, scott, when prosecutors made their argument that these records are relevant to their case, they said some things we'd never heard before. they said the school records

would detail how holmes failed his board exams, his withdrawal from the ph.d. program, that holmes made threats to the university of colorado campus, was banned from the campus, and ordered weapons and body armor. now, according to the prosecutor, all of this happened in june in the weeks and days leading up to the shooting. now, the campus police were informed of the alleged threats by the university. campus police were informed of the threats by holmes. >> pelley: john, this seems to be the first time we've heard that holmes made threats to the university. >> reporter: it is. that was a revelation. and i've spoken to people who are briefed on this investigation, and they have said when the rest of the information comes out, and if it comes out in this process we may learn more sooner about what the university knew and when they knew it about holmes and his violent statements that is going to be very controversial. >> pelley: john, thank you very much. moving on to the presidential

race, four days before the start of the republican convention, new poll numbers give us a good picture of where the race for president stands tonight. have a look. it takes 270 electoral votes to win, and analysis today by our cbs news election team finds there are 237 likely to go to the president or leaning toward him. for mitt romney it's 206. the race will come down to 95 electoral votes that we believe are still up for grabs in eight toss-up states. more than half of those votes are in florida, ohio, and wisconsin. today, a new quinnipiac/cbs news/"new york times" poll of likely voters finds the president ahead in all three states. in florida, he leads governor romney by three points, 49% to 46%. he has a six-point lead in ohio, 50% to 44%. and in wisconsin the home state

of the running mate, paul ryan, the president's-- the president's lead is just two points, 49% to 47%. we have reports tonight from jan crawford and nancy cordes. first, jan with the romney campaign. jan. >> reporter: well, scott, our polls suggest that wisconsin, which the president won by 14 points in 2008, is now up for grabs because he-- because romney picked paul ryan as his running mate. voters also tell us they think that romney is best equipped to handle the issue they care about the most-- the economy. paul ryan has made an impact since he was tapped as romney's v.p., republican enthusiasm for the election considered an indicator of voter turnout is up. in our poll, g.o.p. voters say they're more excited about voting than they were four years ago, and by wide margins over democratic voters, 11 points in ohio, 16 in wisconsin, and 17 in florida. >> the president's policies have

not worked. >> reporter: romney has staked his campaign on the economy, the issue voters say is most important. when asked when candidate would do a better job on the economy, voters give romney the edge in florida and wisconsin and have it tied up in ohio. >> i know this is the best the obama team can do, but we can do better. and we will. ( cheers and applause ). >> reporter: among the majority of voters who say the economy is extremely important, our respondents in all three states say by double digits that romney would do a better job. voters aren't sold on changes to medicare, a reform championed by vice presidential candidate ryan. >> we will end the raid of medicare. we will restore the promise of this program. >> reporter: by a two to one margin, voters favor keeping medicare as it is, rather than changing to a voucher-type program ryan has advocated, and voters in all three states say the president, not romney, would do a better job handling medicare. but when asked if they'd support

some reductions in medicare to reduce the federal deficit, a majority of voters in all three states said yes, 59% in florida, and 58% in ohio and and wisconsin. historically, democrats have had huge advantages on the issues of medicare, but the romney campaign believes they can fight this to a dead heat by talking about the president's health care reform law which, scott, in our poll, remains unpopular. >> pelley: jarng thank you. over the past three weeks, the president has held on toaise six-point lead over governor romney in ohio, but what was a six-point lead in florida is down to three. and in the two weeks since paul ryan became romney's running mate, mr. obama's lead in ryan's home state of wisconsin is down from six points to two. our poll also looked at how the candidates are doing with women voters and nancy cordes has more on that. nancy. >> reporter: scott, this poll was conducted just as that controversy over missouri

congressman todd achin's' abortion remarks was unfolding so it's difficult to know right now what impact if any it will have on the women's vote. what we can say is the president has a commanding lead among women in several battlesground states. in the past month, the obama campaign has stepped up its appeals to women with rallies focused on women's health and ads about abortion rights. >> it's a scary time to be a woman. mitt romney is just so out of touch. >> reporter: but in wisconsin, mr. obama's huge advantage among women has actually shrunk from 23 points in early august to nine points today after native son, paul ryan, joined the republican ticket. in ohio, the gender gap has tightened by eight points, though the president still leads among women there by a healthy 13 points. only in florida has mr. obama's support among women increased by five points, giving him a 12-point advantage among female voters.

it's seniors president struggles with in florida. our poll found he has behind romney by a full 13 points among seniors. in 2008, president obama lost florida seniors to john macane but by a smaller margin, eight points. part of the president's problem is his health care law is unpopular inia florida, particularly among seniors. 50% of floridians over 65 say they disapprove of the law. >> florida seniors are facing a health care crisis. >> reporter: their position has been reinforced by millions of dollars worth of ads from republican groups aimed directly at floridians on medicare. seniors are important to both parties because they are reliable voters. they make up 13% of the population but 16% of the electorate. the obama campaign has been arguing that romney and ryan's plans for medicare would turn off seniors, but, scott, according to our poll, that doesn't appear to be the case right now.

romney is leading by eight points among seniors in ohio and two points among seniors in wisconsin. >> pelley: thanks, nancy. republicans are headed to tampa where their national convention begins on monday, but also headed that way is tropical storm isaac. it is gaining strength south of puerto rico and will likely be a hurricane by monday off florida's west coast. manuel bojorquez is in tampa tonight. >> reporter: inside the tampa bay times forum, republicans were hoping for the best. >> you see outside, big sunshine, blue skies, calm seas, and that's what we're going to have next week. >> reporter: but plans are already in place fair storm that could arrive just as the convention begins. mayor bob buckhorn. >> we literally would take off our convention smat put on our storm hat. that would be really the only logistical difference. >> reporter: republicans will be meeting just yards from tampa's hillsboro river. party officials and media will be at the tampa convention

center, which is inside an area that would be evacuated if winds exceed 96 miles an hour. as many as 4400 delegates and alternates will meet in the forum, which is in a zone that would be evacuated in tides rise above eight feet. 400 buses would shuttle the delegates to safety. >> the city of tampa have been in lockstep together. we'll not make a decision without each other. so all of the players involved in this will be looking at the same data at the same time and makelet appropriate decision together. th>> the final call on whether o suspend any events or the convention itself, where does that come from? >> the rnc. >> reporter: the storm may also affect security plans. 3500 law enforcement officers from across the state are expected in tampa to help, but, scott, they may need to stay in their own towns to help with the hurricane. >> pelley: the rnc, the republican national committee. manuel, thanks very much. one of the navy seals involved

in the killing of osama bin laden was compromised today when his identity was revealed by a cable television network. it is the first time anyone on that mission has been exposed publicly. the man is a recently retired member of seal team 6 who has written the first, first-person account in a book to be published next month. the book, called "no easy day" was written under the pseudonym mark owens. owens' true name was revealed today by fox news and later repeated by the associated press. cbs news does not identify members of classified counter-terrorism units. bob orr has our story. >> reporter: the book is being promoted as the first inside account of the raid on osama bin laden's compound. it's written by one of the u.s. navy seal who is led the assault. while much has already been disclosed about the raid, the publisher of the book, dutton, quotes author mark owen as writing, "it is time to set the

record straight about one of the most important missions in u.s. military history." "no easy day" is the story of the guys, the human toll we paid, and the sacrifices we make to do this dirty job. sources say owen, who is no longer a seal, did not get his manuscript approved as required by the pentagon, the white house, or the cia. owen could face legal problems if the government determines his book discloses classified information that could harm u.s. national security. but his publisher is more concerned that owen himself could face physical danger, retaliation from al qaeda or bin laden sympathizers now that his identity has been revealed by fox news and the associated press. in a statement, dutton said owen has put his life on the line time and again for his country for more than a decade. "we respectfully request that all news organizations consider these fact when deciding whether to pursue or publicize his real

identity." now, legal experts tell us there's a remote chance whoever leaked owen's identity could ultimately be prosecuted for disclosing the name of a convert officer. remember, while he was a seal employed by the pentagon, the bin laden raid was in fact direct by the central intelligence agency. >> pelley: an editor's note-- "60 minutes" has interviewed the seal who wrote the book under the name mark owen. on september 9, "60 minutes" will carry his first-person account on the killing of bin laden. the book, "no easy day," will be released on september 11. chicago's deadly gang wars. why mexican drug gangs invaded the city. and the mysterious makeover of a church painting when cbs evening news continues. exclusive to the milit nation'y

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and every day since, two years ago, the people of bp made a commitment to the gulf. we've worked hard to keep it. bp has paid over twenty-three billion dollars to help people and businesses who were affected, and to cover cleanup costs. today, the beaches and gulf are open for everyone to enjoy -- and many areas are reporting their best tourism seasons in years. we've shared what we've learned with governments and across the industry so we can all produce energy more safely. i want you to know, there's another commitment bp takes just as seriously: our commitment to america. bp supports nearly two-hundred-fifty thousand jobs in communities across the country. we hired three thousand people just last year.

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agent in charge of the drug enforcement administration office here and in four neighboring states. daily turf battles over drugs andrugsand distribution, he saye turning parts of this midwest city into a mexican border town. >> one of the hardest jobs i've had in the last couple of years is to convince our law enforcement partners that we need an enforcement mentality as if we're on the border. >> reporter: jack, the money question here is the influence of the mexican cartels, their influence on the gapings in chicago, and the soaring murder rate right now. >> well, let's take the gloves off on that. we know the majority of the in narcotics here in chicago, the cartels are responsible for. we know that the majority of the murdermurders are gang related. so it is very clear to see the connection and the role. >> reporter: as it stands now, at least three major mexican cartels are battling over control of billions of dollars of marwan acocaine, and increasingly, heroine in this city, including the ultraviolent

zetas and the cartel run by chapo guzman, seen in this picture, back in 1993. >> chapo guzman is the most dangerous criminal in the world. >> reporter: you're saying in essence the most powerful drug lord in the world is operating out of this city. >> i'm saying the most dangerous criminal across all crime in the world is chapo guzman, and this is one of his hubs. >> reporter: for good reason-- chicago's location and easy access to a wide variety of transportation. >> well, you've got to look at chicago from really a perspective of a logistic-- a business logistics. it's an ideal spot to set up shop. >> reporter: to fight back, riley has taken lessons he learned five years ago as agent in charge of the d.e.a.'s el paso office. he's formed a 25-agency strike force featuring state and federal prosecutors, the f.b.i., a.t.f., and local police, that began operation in january.

its focus-- shutting down choke points where gang leadership meets cartel lieutenants. the same strategy he used, he says, to make major arrests on texas border. now he says there's a new border here in chicago that's even a greater challenge. >> i'm telling you, i'm taking this personally. we're going to do something about it. now, this is a marathon. it's not a sprint. and our changes here with the strike force and the way that we look at drug enforcement is going to take time, but it's going to have lasting effects. >> reporter: and more than ever, chicago's problem is turning into a midwest problem. the tonighticles of the cartels spreading drugs and violence, scott, into milwaukee, indianapolis, st. louis, and detroit. >> pelley: armen, thanks very much. cities are spraying to stop the spread of the west nile virus. that story is next. who have used androgel 1%,

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a village in spain has been investigating what looked like an act of vans limp inside a church. how else could you explain the transformation of a decades-old fresco from this to this? turns out it wasn't vandals at all but a parishioner in her 80s. she came forward this week to say she painted over it to try to restore it. she says that she worked in broad daylight with the blessing of her priest. they're having a lot more luck with the biggest sculpture in washington, and we will have a status report a year after the east coast quake next. all multivitamins give me the basics.

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>> pelley: it was one year ago today that an earthquake centered in virginia rocked the east coast. it set the washington monument swaying, and sent tourists scrambling. there were no serious injury, but cracks were discovered in the stone work and the monument remains closed to visitors. the quake also damaged the national cathedral. sharyl attkisson got a look at the repair mission there. >> you see those decorative carved elements? >> reporter: joe alonso has been a stone mason at the wash national cathedral for 27 years. >> now, let me show thu one here. >> reporter: today he took us up 300 feet to view the damage done to the cathedral's 150,000

tons of stone in last year's earthquake. construction started back in 1907, and it was aloffenseo who placed the final stone when it was completed in 1990. >> we laid that stone 83 years to the day, to the moment, i believe, that they laid the first stone. i'd come down probably to the top. >> reporter: today, he's in charge of the cathedral's masons and carvers, and for 21 years, the job was all normal restoration and upkeep. >> then that all changed on august 23, 2011, at 1:53 p.m. >> reporter: you realized you were going to be in charge of getting this mess put back together. >> having worked on the construction of it and just immediately knowing, wow. >> reporter: was that two pieces of stone? >> that was all attached to here, right? it was like this. and it broke free up there, and just started creeping over with the vibrations but the quake ended. you know, again, another couple of seconds, i hate to think what would have happened.

>> reporter: two and a half tons of stone came down. luckily is fell just 30 feet on to the roof of the tower. >> had it gone the war other wat would have fallen almost 200 feet through the roof of the tranaccept the here, and i hate to think what would have happened then. we were very lucky. >> reporter: the other pinnacles also suffered damage. >> we give you thanks for the gift of stone. >> reporter: today, the quake's one-year anniversary was marked with a service, and ringing of the cathedral's bells. and then it seemed fitting that alonso placed the first stone, officially beginning the repair stage that could take $20 million and 10 years. sharyl attkisson, cbs news, washington. >> pelley: and that's the cbs evening news for tonight. for all of us at cbs news all around the world, good night.

captioning sponsored by cbs a beautiful 17-year-old honor student girl hoping for harvard shot and killed in her own bedroom by a man who broke down her front door and apparently came just for her. prince george's county police continue the hunt tonight for her killer. >> reporter: no suspect, no motive, no explanation. it is tough for investigators to admit, but they are really at a loss at this point. amber stanley was going to bed last night in her bedroom right here when someone kicked in the front door, we up the steps, burst into their bedroom