Des Moines, Iowa (CNN) -- Coming off a barely-there victory in the Iowa causes, Mitt Romney vowed Wednesday he will continue to focus his campaign on defeating President Obama, rather than Rick Santorum. Sixth-place finisher Michele Bachmann, meanwhile, scheduled a news conference for 11 a.m., ET, fueling speculation that she will withdraw from the race. Santorum virtually tied Romney Tuesday in the nation's first nominating contest, coming in second by only eight votes in what appears to be the closest-ever margin of victory in a Republican presidential contest, the state Republican Party said early Wednesday. "Of course, people are going to ask us about the differences on our positions on issues and backgrounds and so forth," Romney told CNN Wednesday morning. "But, really, if we talk about what the American people want to hear, it's how we're going to be different than President Obama when it comes to getting the economy going, preserving America's security abroad and making sure we rein in the scale of the federal government. "
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Romney vows to keep his campaign focused on defeating Obama Margin of victory is closest ever for GOP presidential contest
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Santorum's campaign says he proved he's the only conservative who can beat Romney McCain to endorse Romney, senior GOP source says
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Paul says "the message of liberty is appealing to everybody"
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Romney gets 30,015 votes, Santorum collects 30,007
Des Moines
Speaking to supporters in @placeholder early Wednesday, before final results were known, Romney framed the Iowa contest as a "great victory" for him, Santorum and Paul.
Iowa
Iowa
Speaking to supporters in Des Moines early Wednesday, before final results were known, Romney framed the @placeholder contest as a "great victory" for him, Santorum and Paul.
Rick Santorum
Santorum
Santorum
Santorum
Romney has long been a front-runner in Iowa and most national polls, though he also has been stuck at roughly the same percentage of support as a revolving cast of conservative challengers bounced up and down, with @placeholder the latest to rise.
Obama
Obama
"The goal of the campaign has to be to replace @placeholder, but there will be great debate in Republican Party before we are prepared to have a great debate with Barack Obama."
Obama
Obama
"The goal of the campaign has to be to replace Barack Obama, but there will be great debate in Republican Party before we are prepared to have a great debate with @placeholder."
Michele Bachmann
@placeholder, who had hoped for better in Iowa, where she grew up and finished first in a GOP straw poll in the summer before dropping in the polls, also indicate her campaign would continue.