Donald Trump has lived his whole life as though he is trying to prove the theory that all publicity is good publicity. His appearance in court on Tuesday as a criminal defendant will test that cliché to the limit.

This case has certainly put him back in the spotlight. His journey from Mar-a-Lago, his Florida home, to New York was carried live on several US TV stations. He has apparently been discussing with advisers how he should appear throughout the court process - smiling defiantly or looking sombre and serious?

Like it or not this court date is also an election campaign event. The big question is whether Mr Trump can really turn a criminal prosecution into an electoral asset.

Since the indictment against him was announced last week his campaign has been boasting about how much money it has raised (over $8m, they say) and cite opinion polls that suggest his lead over Republican opponents for the presidential nomination has grown.

It is not clear whether such a well-known public figure as Mr Trump will need to have a mugshot photograph taken - but already his former White House spokesman Hogan Gidley has jokingly declared "it will be the most manly, most masculine, most handsome mugshot of all time".

Of course you expect this kind of macho bravado to come from the Trump camp. What is particularly interesting is to watch the way in which Mr Trump's political opponents within the Republican party have felt compelled to come to his defence.

Ron DeSantis, the Florida Governor, said: "The weaponisation of the legal system to advance a political agenda turns the rule of law on its head." And he said he would not assist if there was a request to extradite Mr Trump from Florida to New York

Mr Trump's former Vice-President Mike Pence said the indictment sent a "terrible message" to the world about American justice.

They obviously believe that is what their voters want to hear.

So perhaps Mr Trump can use a criminal trial to his advantage during the electoral primaries when it is loyal Republicans who are voting.

But that same tactic could backfire when it comes to the general election.

Across the US, from Georgia to Wisconsin, I have spoken to very many independents and swing voters who say that while they liked Mr Trump's policies when he was in office, they are now tired of the chaos and drama that surrounds him.

By turning a prosecution into a political spectacle he risks alienating the very voters he would need to win back the White House in November 2024.

John McGuigan is a diehard Trump supporter whom I met outside Trump Tower in Manhattan on Monday.

He told me that he thinks this court case will help Mr Trump's presidential campaign.

He said: "Those who are already convinced Donald Trump is the devil incarnate are not going to be affected by the outcome, nor will the staunch Trump supporters."

But, he thinks, "for those voters who are somewhere in the middle this may end up being more of an asset than a detriment for Trump's 2024 campaign".