The first debate: High stakes for Obama, Romney

Just 34 days out from the November election, there's little argument that tonight's presidential debate - in which President Obama and Mitt Romney will go head-to-head for the first time in this campaign - is a high-stakes affair for both men.

With polls increasingly showing Mr. Obama leading Romney by varying degrees, both nationally and in battleground states, the Colorado match-up offers each candidate a critical opportunity: For the president, it's a chance to shore up his support and solidify what appears to be a recent advantage; Romney, meanwhile, has perhaps his best remaining shot at seizing a much-needed boost in momentum after a disappointing couple of months.

"The stakes are enormous for Mitt Romney," said Steve Schmidt, a Republican strategist who served as a top adviser to 2008 Republican presidential nominee John McCain. "He goes into the debate behind, after a difficult summer, a failed convention, and a series of self-inflicted wounds in September. The hour is growing short to make up ground and come from behind in the swing states where he needs to win if he wants to become elected president."

One debate may not be enough for Romney to take over the lead, analysts say, but a strong performance tonight could certainly put him on the right path - a fact both that will surely weigh deeply on the minds of both candidates.

"I don't think Romney can change the entire trajectory of the campaign at the debate," said Democratic strategist Jamal Simmons. "But he can jump-start that change."

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Despite ongoing efforts by both camps to tamp down debate expectations, there's no question that the event will have bearing on the public consciousness. According to Nielsen estimates, 52.7 million people watched the first match-up between Mr. Obama and McCain in the 2008 presidential contest - and that was down 16 percent from the first presidential debate in 2004, when 62.5 million people tuned in.

Given the stakes, both candidates have been assiduously preparing.

Romney has spent several days over the last month prepping with senior advisers and Ohio Sen. Rob Portman, who is playing the president in preparatory sessions, and dedicated three days during the Democratic National Convention to mock debates with the senator.

And even while the Obama campaign said the president had to cancel several sessions due to events in the Middle East, he headed to Nevada earlier this week to log some serious prep time with 2004 Democratic presidential nominee John Kerry, who is standing in for Romney in practice debates.

Eager though each campaign may be to claim underdog status -- and both have proven exceptionally eager to do just that in recent weeks -- by many accounts it's Romney who has the most ground to make up going into the event.

"Romney doesn't need to try to win the election [tonight]," said Dan Schnur, a former Republican strategist now at the University of Southern California. "There are never magical transformational moments in a presidential debate that's going to fundamentally remake the race. But for a challenger, being on the stage toe-to-toe with an incumbent is an important opportunity to prove that you can be trusted with the responsibilities of the presidency."