Obama loses advantage over McCain, who is now tied with both Democrats

Republican John McCain tried to burnish his economic credentials as a new poll showed he had erased Barack Obama's 10-point advantage in a head-to-head presidential matchup, leaving him essentially tied with both Democratic candidates. In a further boost to McCain, many supporters of Obama and rival Hillary Rodham Clinton are so strongly divided that they say they would rather vote for him if their candidate does not get the Democratic nomination, according to the Associated Press-Ipsos poll released Thursday.