President Joe Biden on Tuesday called for extending a subsidy boost under the Affordable Care Act that is set to expire after 2025, underscoring one of the most immediate health care policy implications of the upcoming election.

The president boasted that he made the ACA — also known as “Obamacare” — “stronger than ever before” by signing into law enhanced subsidies under the American Rescue Plan and the Inflation Reduction Act. That has helped push ACA enrollment to an all-time high of 45 million people, according to government figures.

“I enacted tax credits to save an average of $800 per person per year, reducing health care premiums for millions of working families under the ACA. Those tax credits expire next year,” Biden said during a campaign event in North Carolina. “I’m calling on Congress to make that $800 expanded affordable health care tax credit permanent. Otherwise, millions of Americans with that coverage could lose that coverage.”

Whoever wins in November will have a major say on whether that funding is extended. Biden sees it as a legacy to protect. His Republican rival, Donald Trump, an avowed opponent of the ACA, has not discussed that funding or offered a health care alternative.

Asked how he would handle those subsidies, Trump campaign spokesperson Karoline Leavitt on Tuesday said only that he’s “running to make health care actually affordable, in addition to bringing down inflation, cutting taxes and reducing regulations to put more money back in the pockets of all Americans who have been robbed by Joe Biden’s disastrous economic policies.”

The ACA, signed into law by President Barack Obama in March 2010, includes tax subsidies for people up to 400% of the federal poverty level to obtain coverage. In 2021, Biden and the Democratic-controlled Congress added a provision that assisted people above that level, capping premiums at 8.5% of an individual’s income. The policy has helped millions of people buy insurance and lowered premiums for others who already have it. The nonpartisan Congressional Budget Office has previously estimated that the cap costs about $25 billion per year.

Biden noted Tuesday that “not a single solitary Republican in the Congress voted for” the American Rescue Plan that established the enhanced subsidies for two years, nor the Inflation Reduction Act, which extended them for three years. Republicans objected to many domestic spending provisions in the two measures.

In North Carolina, Biden told a crowd of supporters to assume that if Trump and Republicans win, they will reignite the fight against ACA.

“Trump and his MAGA friends in Congress want to get rid of the ACA and kick these Americans off their health insurance. It’s sick. Now they want to, quote — his word — ‘terminate’ the ACA, as my predecessor says. If that ever happened, we’d also terminate a lot of lives as well,” Biden said. “But we’re not going to let that happen.”

Trump fought during his four years in office to roll back the ACA through executive action, legislation and the courts. He succeeded at zeroing out the penalty for failing to carry insurance, but failed to repeal the law’s insurance regulations and subsidies.

In November 2023, as a presidential candidate, Trump revived his calls for replacing the ACA, criticizing Republicans who voted not to “terminate” it in 2017 when the party fell short in Congress. “It was a low point for the Republican Party, but we should never give up!” he wrote at the time on his social media platform Truth Social. A few days later, after pushback, Trump doubled down, saying: “I don’t want to terminate Obamacare, I want to REPLACE IT with MUCH BETTER HEALTHCARE. Obamacare Sucks!!!”

Ahead of Biden’s speech Tuesday, Trump took aim at his rival: “I’m not running to terminate the ACA, AS CROOKED JOE BUDEN DISINFORMATES AND MISINFORMATES ALL THE TIME,” he wrote on social media, adding in all caps that he wants to “make the ACA, or Obamacare, as it is known, much better, stronger, and far less expensive.”

Trump has not offered a plan to do that, and his campaign didn’t detail one when asked. His party has struggled to come up with health care proposals that maintain the ACA’s benefits — including the protections for pre-existing conditions and the tax credits that extended coverage — at a lower cost.

Senate Minority Leader Mitch McConnell, R-Ky., who fought for years to repeal the ACA, said this month that Trump needs to make his case if he wants Republicans to reopen the issue.

“We had a big fight over that a few years ago,” McConnell told reporters on March 12. “And if he can develop a base for revisiting that issue, obviously we’d take a look at it. But it seems to me that’s largely over.”