Donald Trump’s impending court case marks an historic moment in US politics. He will be the first former president of the United States to face criminal charges and trial by a jury. He and his supporters are already calling the case a political manoeuvre designed to reduce his chances in the 2024 presidential election.

The court case will affect his campaign but it will not exclude him for running for office next year. Early indications suggest that his political base will continue to rally around him. Within hours of the news, his followers were gathering outside his Mar-a-Lago home in Florida to express their support.

The indictment comes after a grand jury in New York agreed that there was enough evidence to charge the former president. The investigation, led by Manhattan district attorney Alvin Bragg, looked into the legality of hush money payments to former adult film star Stormy Daniels.

The exact nature of the charges will not be known until Trump is arraigned next week. According to US reports, he is likely to be accused of more than one count of falsifying business records (classed as a misdemeanour, a lesser crime in the US legal system), after Trump allegedly recorded the payment as a business expense. If found guilty, he could face a fine.

He might also be charged with breaking election campaign laws, which is a more serious felony offence and carries a potential prison sentence. Trump has denied any wrongdoing.

Any criminal charges, or even a jail sentence, would not restrict Trump from running for office under the US constitution. He has previously stated that he would do so even if he was charged. Historically, there are instances of individuals running for president while facing charges or even from a prison cell.

What may affect his chances is the amount of time that he will need to commit to dealing with the charges laid against him. To date, his campaign has been relatively quiet, but it will need to gain momentum in the lead up to the Republican convention in July 2024.

On March 25 and 26, Trump held his first campaign rally for the 2024 election at Waco, Texas. Despite predicting that he would be arrested, thousands turned up to show their support.

Claiming that the 2024 election would be “the final battle”, Trump criticised the prospects of potential challengers, such as Florida’s governor, Ron DeSantis, and stated that the investigation was like something out of Stalinist Russia. He told his supporters “from the beginning it has been one witch-hunt and phony investigation after another”.

Trump’s immense popularity with Republicans is unlikely to be damaged by any indictment resulting from the New York investigation. One poll showed that most Republicans believe that the investigation is politically motivated, while another indicated that most Americans think that Trump will be acquitted of the charges.

The Harvard/Harris poll shows that popular support for the charges is split along party lines – 80% of Democrats believe he should be indicted, while 80% of Republicans believe he should not. And 57% of Republicans think a trial could help Trump in the election run.

Republicans lawmakers have already come out in support of Trump. House Speaker Kevin McCarthy said that the indictment was an “unprecedented abuse of power”. House Majority Leader Steve Scalise tweeted that the charges were “one of the clearest examples of extremist Democrats weaponizing government to attack their political opponents”.

Even Trump’s potential rivals for the 2024 nomination have come out in support of the former president. DeSantis said the charges were “un-American” and a “weaponization of the legal system”, while Pence called the indictment “an outrage”.

For many observers, the question remains: why does Trump still figure so highly in the Republican polls after everything that has happened?

A Harvard/Harris poll from mid March, shows that Trump has increased his favourability among Republican voters to 50%, giving him a 26-point lead over DeSantis, if the presidential nomination was decided now. Former vice president Mike Pence is a distant third with just 7%. A more recent Fox News poll makes the gap between Trump and DeSantis to be even greater at 30%.

Worryingly for Democrats, those polled of all political persuasions give Trump a four-point lead over Biden. There is a glimmer of hope for the Democrats, though, in that 14% of those polled were undecided on either Trump or Biden. It’s a significant number, and those individuals will be key to deciding who wins the election in November next year.

Trump’s immense popularity with Republicans is unlikely to be damaged by any indictment resulting from the New York investigation. This is because the Republican Party is still the party of Donald Trump. His base support has never fluctuated since 2016. Many of them feel he stands up for them when no-one else does.

His Republican opponents, such as DeSantis, are trying to outdo Trump at being Trump. But they are pale imitations, and Trump knows this.

Earlier this year, Trump told the crowd at the Conservative Political Action Conference: “I am your warrior, I am your justice.” And they believe that. His supporters believe that he is the only person capable of protecting their values and way of life.

In a supporting speech at Waco, Trump-ally, Representative Marjorie Taylor-Greene said: “Trump is the man for the hour. He’s the only man who can take on Washington in the times that we live in.”

While the indictment might make some moderate Republicans rethink their loyalty to the former president, his base will back him to the bitter end.