So now the Republican presidential candidates can head home from Las Vegas, start to ease back on campaigning for a bit, but count the days to Iowa.

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The final debate of 2015 will set the field for the final run into the first electoral test for the campaigns.

In a few days the opinion polls will deliver a picture of what the watching public thought, and then most people will turn their attention to the holidays, to the New Year's celebrations and just getting through the first few days of January.

There will still be a few more coughs and splutters, a few more political fights and arguments but for many people their attention will be elsewhere.

And before you know it, they'll be gathering to caucus in Iowa, delivering their verdict, propelling someone closer to the White House.

Donald Trump will be pleased. He enjoys a commanding lead in national polls.

The campaign which was expected to be a summer fling with the American people has become an affair to remember.

Iowa might not deliver the win he wants - but it'll put him in a strong position going into the second nominating contest, the New Hampshire primary.

He had an OK debate in Las Vegas, looking rattled at some of the attacks which was a first and never clearly answered some questions but that won't scare off his support.

He also ruled out an independent run, saying he would support the Republican candidate, clearly expecting it to be him.


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Ted Cruz will be delighted. He's timed his run perfectly. From polling just a few percent - he now leads many polls in Iowa. He believes Donald Trump's support will eventually move to him. The Texas senator spent the debate launching attacks on Marco Rubio.

That suggests he sees him as his biggest threat. He may not be wrong. These contests often become 'outsider' versus 'establishment'. And Cruz is so widely disliked in the Republican Party, he wears the outsider label as a badge of honour.

Rubio himself continues to do OK. But looking at the contest, it's not clear where he scores the first primary win. And if he doesn't strike in the first four, then the Florida senator will struggle to continue, even if he is seen now as the most likely 'establishment' candidate to win.

On the stage in Las Vegas, Jeb Bush had his best night, and the best line of the night when he told Donald Trump: "You're never going to be president of the United States by insulting your way to the presidency."

It must be frustrating for his supporters, wondering where this guy was for the past few months. His campaign remains mired in single figures in the polls and the former Florida governor really needs a top three finish in Iowa to keep going.


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Kentucky Senator Rand Paul also had his best debate performance, helped by loud cheers in the hall when he tackled civil liberty issues. He has support in Iowa, thanks to his dad's presidential campaign four years ago and will see his numbers rise after the debate.

Chris Christie remains the hardest one to judge. He won't do well in Iowa but poll numbers suggest things will be different in New Hampshire. He had a solid night. Clearly the line about him being a former federal prosecutor tested well in some focus group. He hammered it all night.

The biggest loser was Ben Carson, who showed nothing to stop his drop in the polls. The neurosurgeon struggles on foreign policy and national security. Which is what the debate was about and two of the biggest tasks for any president. He'll do OK in Iowa, but OK won't be enough.

Ohio Governor John Kasich simply cannot convince Republican voters to give him another look. And Carly Fiorina remains a middle-order candidate. Her best moment in these debates has clearly passed.

The candidates can all now head off and spend some time with their family over the holidays. With many of them knowing they're going to get a lot more time with them after Iowa.

Trump continues to poll well despite courting controversy with his views on Muslims and refugees [John Locher/AP] 

Source: Al Jazeera