There's no better example of the see-saw of the undecided voter than 58-year-old Linda Brode. She's a registered republican in Tamaqua, Penn., a small, working-class town in a battleground state.
"I have no clue who do vote for, and I've usually made up my mind by now," she told CBS News correspondent Kelly Wallace.
A divorced mother of one, she voted for Bill Clinton and George Bush.
Two weeks ago, she was blown away watching Barack Obama's acceptance speech.
But then she heard Sarah Palin. And now won't make up her mind until all the candidates face-off.
"These debates are very important to people, and I know I'm not alone in thinking this way," she said.
According to the latest CBS News poll, 55 percent of undecided voters are women like Linda. But of those who have made up their minds since the conventions, 28 percent volunteered Sarah Palin as the reason for their decision - more than any other factor. Terri Klingaman is a registered republican who was undecided.
"She sealed the deal with her speech; she really did," Klingaman said.
"I guess because of her - the way she was brought up and her family values as well," Koles said.
Traditionally, it's the top of the ticket that sways undecided voters. The emergence of Palin is challenging that assumption - for now.