JUSTIN WEBB: Trump's supporters would vote for him if he was in jail

After victory at the Iowa caucus, Donald Trump spent part of yesterday in a New York court.

To his supporters, such scenes go with the territory. Seeing their leader defending a $10million defamation case is just the price of doing business with him.

Whatever his legal problems – Trump is facing a list of charges that could put him in prison for around 700 years – his political business is thriving.

True, his opponents are adamant that there is still a race for the Republican presidential nomination before the final election in November.

But after yesterday's court appearance – in a case in which he has already been found to have defamed a woman he had sexually assaulted – he headed to New Hampshire, the next primary state, with the aim of finishing off his wounded opponents.

That sentence is enough to tell you that this man is more than Teflon. Nothing bad attaches to him for long – indeed, he uses the bad as a political asset. He was a loser. Now he is back to winning.

After failing to secure re-election in 2020, Trump seemed to be on the way out. Many of those who had backed him had started to look elsewhere.

But then came the four sets of criminal charges. At the time, some pundits wondered whether they would in fact bolster his chances. Now we know the answer.

Iowa is a first in America. After the polls and TV talking-heads have had their say, this frozen state provides the first opportunity for real people to choose the presidential candidate.

This year, the famous Iowa caucus has become the coldest in the state's history. And when I say 'cold', I mean it. With wind chill, it has been -40C. To go from a building to your car actually hurts. Your face freezes. Your lips, too.

The road from Chicago to Des Moines, which I had to take as all the flights were cancelled, was littered with those huge American trucks you see in movies, spun around at crazy angles.

The journey should take five hours, but it took me a day. Signs by the road say simply: 'Travel is not advised.'

You're on your own. Crash and you may die quickly of cold in snow. Very American. Very bracing.

The first question on caucus night, then, was whether significant numbers of people might stay at home. Going outside would be too much effort. You see, in a caucus, people have to do more than just vote and rush back to the car. The process involves speeches and participation.

So the second question was: Could we see from the result whose supporters were more enthusiastic, more willing to risk frostbite? Trump had said: 'You can't sit at home. Even if you're as sick as a dog, you say, 'Darling, I gotta make it.' Even if you vote and then pass away, it's worth it!'

Was he joking? Sometimes with Trump, it's difficult to say. But now we can argue his supporters seem to have taken him seriously, doing as he suggested. Now it is difficult for anyone to catch him.

Nikki Haley, former governor of South Carolina and Trump's UN ambassador, needed to come second and claim the mantle of main challenger to Trump. She failed. Instead, tough-talking Florida governor Ron DeSantis came second. But he now faces a contest in New Hampshire in which he will almost certainly be trounced, because New Hampshire's more suburban and independent primary voters don't like him.

Iowa's result is deeply frustrating for Haley. The polls suggest she would beat easily Joe Biden in the presidential election – but she has to become the Republican candidate first. And her chances of that are melting away.

So Trump steams ahead. And even if he were convicted – perhaps jailed – before the November election, his supporters tell pollsters they will stick with him.

Not that the wider nation will necessarily think that way. Trump's chances of winning the final contest against Biden might be significantly reduced in the event of a criminal conviction.

But the Republican party seems to have made up its mind. Biden v Trump, round two. The first modern presidential contest with two former presidents are likely to be on the ticket – and the oldest candidates in history as well.

These men want to do battle, even if that depresses their electorate. Even if it damages America.