Who will win Wednesday's presidential debate?

WASHINGTON (CNN) -- Two days before the first debate between President Barack Obama and Republican nominee Mitt Romney, a new poll indicates that most Americans see the GOP challenger as the underdog in the first showdown.

According to a ABC News/Washington Post national poll released Monday, 55% of likely voters say they think the president will win the debate, with 31% saying that Romney will be victorious. The findings on this question from the new survey are in-line with a CNN/ORC International poll conducted right after the Democratic convention earlier this month, where by 59%-34%, likely voters said Obama rather than the former Massachusetts governor would be more likely to do a better job in the October showdowns.

Wednesday night's debate in Denver, Colorado is the first of three between the president and Romney. Vice President Joe Biden and Rep. Paul Ryan of Wisconsin, Romney's running mate, face off once as well.

According to the Washington Post poll, 49% of likely voters say if the election were held today, they'd vote for the president, with 47% saying they'd vote for Romney. The president's two point margin is within the survey's sampling error. A new Politico/George Washington University Battleground poll also released Monday also indicates it 49% for Obama and 47% for Romney among likely voters nationwide.

The two new surveys follow a Fox News poll released late last week which indicated a five point advantage for the president. A CNN Poll of Polls which averages all three surveys together puts Obama at 49% and Romney at 46% among likely voters.

The ABC News/Washington Post poll was conducted Sept. 26-29, with 1,001 adults nationwide, including 929 registered voters and 813 likely voters, questioned by telephone. The survey's sampling error for likely voters is plus or minus four percentage points.

The Politico/George Washington University Battleground poll was conducted Sept. 24-27, with 1,000 adults nationwide questioned by telephone. The survey's overall sampling error is plus or minus 3.1 percentage points.