That's prompted some women conservative columnists, who once supported her, to call for her to step down for the good of the party.
Governor Palin's favorability ratings among independents are also going down as her unfavorable ratings are on the rise.
Friday night's debate in Oxford, Miss., which did happen despite McCain's calls to have it postponed, has also helped Obama.
A number of postdebate polls show that most viewers thought the Illinois senator did a "better job."
"The economy is the issue that looks like it's going to dictate this election," says Darrell West, the director of governance studies at the Brookings Institution in Washington. "And Obama won those parts of the debate that he needed to win."
McCain's demeanor, particularly during the second part of the debate, may also have hurt him with some independent voters.
"There were times McCain came across as too angry," says Mr. West. "That's a style of delivery that's going to scare some undecided voters, and it's also a style that women don't like, and there are more undecided women than men."
Some analysts don't believe the debate will impact that race all that much even though it highlighted the candidates' differing visions.