Former president Donald Trump has told Christians that if they vote for him this November, "in four years, you don't have to vote again. We'll have it fixed so good, you're not gonna have to vote."

It was not clear what the former president meant by his remarks, in an election campaign where his Democratic opponents accuse him of being a threat to democracy, and after his attempt to overturn his 2020 defeat to President Joe Biden, an effort that led to the deadly insurrection at the US Capitol on January 6, 2021.

The Trump campaign did not immediately respond to a request for clarification of his comments.

Trump was speaking at an event organised by the conservative group Turning Point Action in West Palm Beach, Florida.

Trump said: "Christians, get out and vote, just this time. You won't have to do it anymore.

"Four more years, you know what, it will be fixed, it will be fine, you won't have to vote anymore, my beautiful Christians."

"I love you Christians. I'm a Christian. I love you, get out, you gotta get out and vote."

Trump campaign spokesperson Steven Cheung did not directly address Trump's remarks when asked to clarify them.

Cheung said Trump "was talking about uniting this country," and blamed "the divisive political environment" on the attempted assassination of Trump two weeks ago. Investigators have yet to give a motive for why the 20-year-old gunman opened fire on Trump.

In an interview in December, Trump said that if he won the November 5 election he would be a dictator, but only on "day one", to close the southern border with Mexico and expand oil drilling.

Democrats have seized on that comment. Trump has since said the remarks were a joke.

Republican presidential candidate former President Donald Trump speaks at the Bitcoin 2024 Conference. – AP

If Trump wins a second term in the White House, he can serve only four more years as president. US presidents are limited to two terms, consecutive or not, under the US Constitution.

In May, speaking at a National Rifle Association gathering, Trump quipped about serving more than two terms as president.

He referred to the presidency of Franklin D Roosevelt, a Democrat, the only president to serve more than two terms. The two-term limit was added after Roosevelt's presidency.

"You know, FDR, 16 years – almost 16 years – he was four terms. I don't know, are we going to be considered three-term? Or two-term?" Trump asked the NRA crowd.

Trump's remarks pointed to the need for both parties to energise their base voters ahead of what will likely be a closely fought election.

The race has abruptly tightened after the decision by Biden to end his reelection bid and with his vice president, Kamala Harris, becoming the presumptive Democratic nominee.

Recent opinion polls show Trump's significant lead over Biden has been largely erased since the torch was passed to Harris.

Jason Singer, a Harris campaign spokesperson, in a statement did not directly address Trump's remarks about Christians not having to vote again.

Singer described Trump's overall speech as "bizarre" and "backward looking".

Donald Trump stands with his vice presidential nominee JD Vance in Grand Rapids, Michigan. – Reuters

Trump next takes his campaign back to Minnesota, a state that has favoured Democrats but that the former president thinks could be in his reach this year.

Trump is set to hold a rally in St Cloud, Minnesota, this time bringing along his running mate JD Vance and the expectation Trump will face Vice-President Kamala Harris in November instead of Biden.

He was speaking at a bitcoin conference in Nashville, Tennessee, earlier in the day, where he called for America to embrace cryptocurrency to stop other countries from dominating in the technology.

In May, Trump headlined a GOP fundraiser in St Paul, where he boasted he could win the state and made explicit appeals to the iron mining range in northeast Minnesota, where he hopes a heavy population of blue-collar and union workers will shift to Republicans after years of being solidly Democratic.

That’s also a group of potential voters that Trump’s campaign has seen Vance, an Ohio senator, as being particularly helpful in trying to reach, with his own roots in a Midwestern Rust Belt city.

Appeal to Midwesterners and union workers is something that has also helped Minnesota Governor Tim Walz land on the list of about a dozen Democrats who are being vetted to potentially be Harris’ running mate.

Minnesota is a state where Trump in 2016 was 1.5 percentage points shy of defeating Democrat Hillary Clinton. But four years later, Biden expanded the Democratic win, defeating Trump by more than 7 percentage points.

But the Republican former president has been bullish on the state.

In a memo last month to the campaign and the Republican National Committee, Trump’s political director James Blair called Minnesota a battleground where Trump compared favourably to Biden, their opponent at the time, and said the campaign was hiring staff there and in the process of opening eight offices in the state.

The campaign didn't clarify whether those eight offices were open.

Earlier this month, Republican congressional candidate Tayler Rahm dropped out of his primary race and began serving as a senior adviser to Trump’s campaign in the state.

“The Biden/Harris Administration has been so disastrous, and Democrats are in such disarray, that not only is President Trump leading in every traditional battleground state, but longtime blue states such as Minnesota, Virginia and New Jersey are in play,” Karoline Leavitt, the national press secretary for Trump’s campaign, said.