Many commentators had predicted Palin had the most to lose in St. Louis, based on recent television interviews. But Palin stared steadily at the camera to make her points, didn't appear flustered and peppered her strongly personal answers with a folksy accent.

In contrast, Biden was relentless in his criticism of Republican presidential nominee John McCain and in his attempts to tie the McCain-Palin ticket to the Bush administration, which is enjoying record unpopularity in the polls. He also strongly defended Democratic presidential nominee Barack Obama.

Asked what they would do if either a President Obama or McCain died in office, Biden said, "It would be a national tragedy of historic proportions, if it were to happen, but ... I would carry out Barack Obama's policies -- his policies of reinstating the middle class, making sure that they get a fair break ... affordable health insurance ... serious tax breaks ... a foreign policy that ends this war in Iraq ... (and) that goes after the one mission the American public gave the president after 9/11 -- to get and capture or kill (terror leader Osama) bin Laden and to eliminate al-Qaida ... "

Palin said she would continue McCain's policies.

"As for disagreeing with John McCain and how our administration would work, what do you expect? A team of mavericks. Of course we're not going to agree a 100 percent on everything," she said.

"What I would do also if that were to ever happen, though, is to continue the good work that he is so committed to, and that's putting government back on the side of the people and get rid of the greed and the corruption on Wall Street and in Washington."

At one point, Biden teared up when, in response to a remark by Palin about her experience as a mom, he talked about raising his family after the auto accident in which his first wife died and a son was critically injured.