Obama Pulls Ahead of Romney in New Poll

And now we move on to big news for the obama campaign. Just 57 days to go before "your voice, your vote" and the latest poll shows the president pulling ahead, that post-convention bounce. He is now... See More

And now we move on to big news for the obama campaign. Just 57 days to go before "your voice, your vote" and the latest poll shows the president pulling ahead, that post-convention bounce. He is now leading governor romney by six points as both candidates set their sights on the handful of voters still making up their minds, so who are they? Abc's david muir is in the swing state of ohio tonight. David? Reporter: Diane, that small handful of voters you speak of by some estimates 7 million americans who could decide this race. Tonight, what's behind the president's bounce and this year why even a smallounce could determine the winner in november. Here is mitt romney greeted by supporters and by the new poll numbers. President obama pulling ahead. Before the democratic convention that same poll, the two men tied at 48 apiece. Tonight, the president with a six-point lead. Strategists on both sides recognize that in this election year even a small shift is significant. Four-point leader is as significant as a 10 to 12-point lead 20 years ago. Reporter: Matt dowd has advised candidates for both parties and argues the country is more polarized now. Only a tiny slice of americans have yet to decide. Today we only have 6% of people who are truly swing and truly persuadable. So if you get a four, five or six-point bounce it means you're maximizing what absolute you can get. Reporter: What led to this bounce? It points to michelle obama's performance and bill clinton and those who chose obama last time who still like him but are disappointed. No president, no president, not me, not any of my predecessors, no one could have fully repaired all the damage that he found in just four years. Reporter: The romney campaign tonight calling the bounce a, quote, sugar high from the convention, that the reality of the obama economy hasn't changed. To say it's nearly impossible mathematically for governor romney to win the white house without winning right here in ohio. This is right here in the factory. Romney now with 15 ads up in nine battleground states but the number most important october 3rd debating president obama less than one month until that first debate. How important are these debates going to be? Well, I think the debates very important particularly when you have a small sliver of the electorate that has yet to make up their mind. Reporter: The romney campaign acledging to me today just how important those debates are going to be and in particular that first debate, diane, if these poll numbers hold it will be a make-or-break moment for romney. The romney campaign tonight not ceding an inch and in the battle of ground of nevada this time tomorrow, diane. All right, thank you, david. THE DEBATE IS AGAIN OCTOBER 3rd.