Sen. Barack Obama got no lasting boost from his ballyhooed trip overseas last week, according to national and swing state polls released Thursday.

And Republican Sen. John McCain may have benefited from his Democratic rival's visit to Iraq, Afghanistan and other countries, said Frank Newport, the Gallup Poll editor in chief. "McCain voters may have been energized," he said. "They said they were paying more attention to the race."

However, many experts warned not to take seriously polls in the summers of presidential election years.

Gallup's daily sampling of 2,682 registered voters found Obama with a 45 to 44 percent lead over McCain on Monday through Wednesday, a narrower margin than Obama had when he began his trip.

New Quinnipiac Polling Institute surveys Thursday found that Obama's lead in three key swing states has dropped. Obama leads McCain by 7 percentage points in Pennsylvania, down from 12 points in June. His lead in Ohio and Florida is down to 2 points, which is within the margin of error. Last month, he led in Ohio by 6 points and Florida by 4 points.

HE'S ONE OF A KIND

How many governors endorse one candidate for president and then, even before the election, leave the door open to working in his opponent's administration? One so far: Arnold Schwarzenegger.

He boasts that he's California's first "post-partisan" governor.

He endorsed McCain, his friend and fellow Republican, and will appear on the Arizona senator's behalf at the Republican National Convention this summer. Yet he also has made it clear that Obama wouldn't be so bad. He commonly answers questions about global warming and other topics by saying that either candidate will be a big improvement over President Bush.

Earlier this month, Schwarzenegger responded to a hypothetical question by saying he wouldn't rule out a job in an Obama administration. "I would take his call now, I will take his call when he's president -- any time," he said. Schwarzenegger added that he intends to finish the last term he's allowed as governor, which ends in 2010.

THE FIGHT IS ON IN FLORIDA

For those still wondering whether Obama will battle for Florida, consider this: He has spent more money on advertising in the state than in any other over the past two months, for a total of $5 million. McCain's advertising budget in Florida so far: $0.

The findings by the University of Wisconsin Advertising Project reflect Obama's rapid build-up in a state he once shunned because its primary broke national party rules. Since Obama wrapped up the Democratic nomination on June 3, his campaign has hired 200 people and opened 13 offices in Florida, with more to come. Both candidates will campaign in Florida today and Saturday.

'VOTE BOTH' CALLS IT QUITS

An organized effort to persuade Obama to make Hillary Rodham Clinton his running mate has shut down.

The two former Clinton staffers who started the group "Vote Both" concede it just isn't likely to happen.

The Obama campaign isn't commenting on the vice-presidential selection process. Advisers for both say Clinton is likely to speak on the Democratic convention's second night, which is 88 years to the day women earned the right to vote.

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