Biden to supporters: 'If Trump wasn't running, I'm not sure I'd be running'

President Biden on Tuesday told supporters he's not sure if he would be seeking a second term in the White House in 2024 if former President Donald Trump wasn't trying to win back his old job.

"If Trump wasn't running, I'm not sure I'd be running. But we cannot let him win for the sake of the country," the president said at a fundraiser at a private home near Boston, Massachusetts, according to a pool report.

Biden's candid comments about his reasons for running for re-election came as he reiterated what he and Democrats have emphasized is the threat Trump poses to American democracy if he wins back the White House. 

"Trump’s not even hiding the ball anymore. He’s telling us what he’s going to do. He’s making no bones about it," Biden warned.

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Spotlighting Trump's threat to democracy has been a central theme for Biden dating back to the April 2019 launch of his 2020 presidential campaign.

The president, at the fundraiser, also highlighted Trump's recent renewed calls to scrap the Affordable Care Act, the sweeping health care law passed during Biden's tenure as vice president during then-President Obama's administration.

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The fundraiser, one of three the president was headlining in the Boston area on Tuesday, comes as the president kicked off a fundraising sprint to close the year, to build resources for what will certainly be an expensive re-election effort in 2024.

The president's remark suggests that Biden may not have run for another four years in the White House if Trump had decided against a 2024 bid.

After his comments at the fundraiser made plenty of headlines, the president was asked as he returned to the White House on Tuesday evening if he would be seeking a second term if Trump wasn't running.

"I expect so. But, look, he is running and I just – I have to run," Biden said. 

Asked if he'd drop out if Trump left the race, the president said "no, not now."

Trump remains the commanding front-runner for the GOP presidential nomination as he makes his third straight White House run.

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He made history earlier this year as the first former or current president to be indicted for a crime, but his four indictments – including in federal court in Washington, D.C., and in Fulton County court in Georgia on charges he tried to overturn his 2020 presidential election loss – have only fueled his support among Republican voters. Trump currently holds a large double-digit lead over the rest of the shrinking field of GOP rivals for the nomination.

Biden made history in 2020 as the oldest person elected president, as he defeated Trump. 

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The now 81-year-old Biden has long viewed himself as the Democrats' best shot at keeping Trump from winning back the White House.

But Biden continues to suffer from underwater approval ratings among many Americans and faces concerns – not just from Republicans and independents but also from Democrats – over his physical and mental stamina.

While the president is the commanding front-runner for his party’s 2024 nomination, polls indicate that many Americans – including plenty of Democrats – don’t want the president to seek a second term in the White House. 

Those same surveys spotlight that voters are far from thrilled with the likely prospect of a rematch between Biden and Trump.

Fox News' Kate Sprague, Sarah Tobianski, and Kelly Phares contributed to this report

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