Barack Obama actually said...
If we are really serious about winning this election, Democrats, then we can't live in fear of losing it. This party, the party of Jefferson and Jackson, of Roosevelt and Kennedy has always made the biggest difference in the lives of the American people when we led not by polls, but by principle, a party that doesn't just offer change as a slogan, but real, meaningful change, change that America can believe in.
Context
Obama emphasizes the importance of leading by principle rather than polls in order to win the election.
11/11/2007