US President Barack Obama and Republican candidate Mitt Romney are set to meet in their third and final debate ahead of 6 November’s presidential election – focusing on foreign policy.

Libya and Iran will likely feature, as well as terrorism, a rising China and the wars in Afghanistan and Syria.

The 90-minute televised event in Boca Raton, Florida will be their last head-to-head clash before the election and is expected to draw 60 million viewers.

An NBC poll on Sunday put the men in a dead heat, each with 47% support.

Monday’s debate at Lynn University will begin at 21:00 EDT and see the candidates seated at desks in a contest moderated by CBS News’ veteran anchorman Bob Schieffer.

Barack Obama will be aiming to stress his commander-in-chief credentials as the man who neutralized Osama Bin Laden and ended the Iraq war, analysts say: He will be trying to portray Mitt Romney as lacking the experience to steer the nation through a crisis.

For his part, Mitt Romney is expected to push his campaign’s position that US foreign policy is “unravelling before our very eyes”.

At a confrontational second debate in New York last week, Mitt Romney said the 11 September attack on the US consulate in Benghazi – which killed four Americans including the US ambassador to Libya Christopher Stevens – and wider anti-American violence in the Middle East were symptomatic of that decline.

The Republican candidate accused Barack Obama of initially downplaying the role of radical Islamists in the Benghazi attack – in order to protect a successful anti-terrorist track record.

Barack Obama countered that he had denounced the killing as “an act of terror”, snapping that Mitt Romney should “check the transcript” rather than trying to score political points from the tragedy.

The former Massachusetts governor has accused the president of not being firm enough in support of America’s principal Middle Eastern ally, Israel.

Barack Obama has a chilly relationship with Israeli Prime Minister Benjamin Netanyahu, and has refused to bow to Israeli pressure to issue ultimatums to Iran over its nuclear programme.

But while the president routinely says a nuclear-armed Iran is unacceptable, he also praises the people of Iran.

On such issues, Mitt Romney has not spelt out what he would do differently – except be tougher. He has raised Iran’s quest for nuclear weapons – which Tehran denies – as evidence of President Barack Obama’s lack of leadership.

During the weekend, reports surfaced that the White House was open to one-on-one talks with Iran – but that there were no talks planned.

Mitt Romney will likely use the reports to show Barack Obama as weak.

While Barack Obama sees China as a competitor in the global market, Mitt Romney has been more outspoken on the emerging global superpower, saying Beijing cheats by manipulating the value of its currency against the US dollar – and that he will crack down.

But the millionaire businessman has also stumbled on international issues, managing to upset as many people as he impressed during a tour of Europe and Israel this summer.

Barack Obama spent the weekend preparing for the debate at the presidential retreat in Camp David in Maryland’s Catoctin mountains.

His opponent acclimatized in Florida with the same intensive preparations that have taken up much of his time this month.

A lackluster performance by Barack Obama in the opening debate in Denver, Colorado, on 3 October gave Mitt Romney a campaign boost, with polls perceiving the challenger as having won the debate by a wide margin.

But in their second face-off in New York last week, a more aggressive Barack Obama buried the memory of a poor first showing as he came out swinging on the economy, tax and foreign policy.

After Monday night’s showdown, both candidates will be returning to the campaign trail for a grueling final two weeks of wooing voters in swing states.

While analysts suggest the contests in some 40 states are as good as over, battles in states like Ohio, Florida and Virginia remain in the balance – and the key issues for many would-be voters remain the economy and jobs.

Much as Monday’s debate is about foreign policy, the candidates will use any opportunity to highlight the strengths of their economic policies, analysts say.