US elections: Barack Obama and Mitt Romney in virtual lockdown as they prepare for first of three televised debates

Debates may be a make-or-break moment for Mitt Romney.

Polls show a tight race between Mitt Romney, left, and Barack Obama

Against a background buzz of mixed polling numbers and increased sniping over foreign policy, the two candidates for the American presidency were in virtual lockdown today cramming for Wednesday night’s televised debates that may be a make-or-break moment for the challenger, Mitt Romney.

Mr Romney, who used a column in the Wall Street Journal to target President Barack Obama for his administration’s response to the killing of US Ambassador Christopher Stevens in Libya two weeks ago, was already Denver, the site of tomorrow night’s debate. Team Obama was behind closed doors in a desert resort close to Las Vegas in near permanent debate rehearsal with Senator John Kerry playing Mr Romney.

While the theme at Wednesday’s debate – the first of three between the presidential contenders – will be domestic policy, Mr Romney is likely to raise the recent turmoil in Libya and Egypt and question Mr Obama’s handling of it. “Our country seems to be at the mercy of events rather than shaping them,” Mr Romney wrote in the Journal. “We’re not moving them in a direction that protects our people or our allies.”

A flurry of new polls ahead of the debates underscored the high stakes for both men, particularly Mr Romney who has suffered serial missteps since the Republican convention in Tampa. A new Washington Post survey showed Mr Obama leading him 52 to 41 per cent in the handful of battleground states that will decide the election. By a margin of 55 to 31 per cent respondents expected Mr Obama to win the debates.

But a poll for Politico.com showed only a two-point gap between the men – within the statistical margin of error – in the battlegrounds with Mr Obama scoring 49 per cent to Mr Romney’s 47 per cent. “The basic underpinnings of this race are just not changing, and that’s what’s going to keep this a very close race,” argued pollster Ed Goeas of the Tarrance Group, a Republican who helped compose the survey.

Nonetheless, it remains clear that it is Mr Romney who has biggest hill to climb with some party insiders fearing that a poor performance tomorrow could lead some supporters to consider him a lost cause, which in turn could lead to a drying up of contributions and fewer outside groups advertising for him.

“For Romney, it’s a double goal that he has: He’s got to get that likability up, particularly among women,” argued Celinda Lake, a Democratic pollster who also helped with the Poltico survey. “And he’s got to draw a sharp contrast on what he’d do on the economy. That’s very difficult to do simultaneously… It’s hard to maintain likability when you’re being an attack dog.”

Mr Obama attempted to downplay expectations for himself while addressing a rally in Las Vegas late yesterday. “I’m looking forward to it. I know folks in the media are speculating already on who’s going to have the best zingers... and who's going to put the most points on the board,” he offered, before adding to a mixture of laughter and applause: “Governor Romney, he’s a good debater, I’m just OK.”

The president’s debate-prep team were said last night to be focusing in particular on persuading him to keep his answers short tomorrow and not to expand too lengthily on topics that might send viewers to sleep and to avoid appearing either professorial on the stage or even condescending to his sparring partner.