Next Wednesday's presidential debate is possibly Mitt Romney’s last opportunity to win this election, said an expert. With President Barack Obama leading in polls, the burden's on Romney to prove that he can bring back the economy despite not providing a solid plan to do so.

Tom Hollihan, a communication professor at the University of Southern California, has served as a consultant to many political candidates, elected officials, and business leaders. In the upcoming debate, he envisions that Obama’s argument will be based on the achievements and the work that has yet to be done. Hollihan said Romney has a much more difficult circumstance.

“He has got to have a really successful first debate,” Hollihan said, “Or the election is probably over in my opinion.”

He said Romney’s challenge is greater considering that many voters say he's distanced from ordinary people.

“Let’s face it, he [Obama] appeals to young people and person of color and person of lower economic backgrounds,” Hollihan said, “Romney is much more a candidate of white men and wealthy elites.”

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Wednesday will be Romney’s first face-to-face conversation with Obama in the presidential election.

Romney told Fox News, “The president is a very eloquent, gifted speaker. He’ll do just fine. I’ve never been in a presidential debate like this and it will be a new experience.”

Early voting has started in many states, and Romney can’t afford to make a mistake, said Hollihan. Romney must peg the residual weakness of the U.S. economy on Obama.

“If you look at the historical model of election outcomes,” Hollihan said, “it’s very difficult for a president to be reelected, when the state of economy is as bad as it is.”

But Romney hasn’t provided a sufficient and efficient plan to fix the economy. As a result, Hollihan said, Obama has defined Romney more successfully than Romney has defined himself, which is four more years of old-styled Republican tax cuts that trickle down the economy. To connect with the voters’ emotion and their rational judgment away from the emotion, candidates have to define themselves and their opponents.

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To prepare for the big debate, both candidates are working with debate coaches and going over position papers. From his experience working with candidates, Hollihan said candidates have to make sure that they can express their own positions forcefully and effectively and practice the argument and expected attacks from the opponent. Another thing that candidates are taught to do is to listen to the question quickly and briefly answer it, and then shift the focus to the point they want to make that they've spent plenty of time studying.

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