Vice-President Kamala Harris may have received another last-minute helping hand from Republicans after the House speaker, Mike Johnson, said there would be “massive” healthcare changes if Donald Trump wins next Tuesday, including abolishing Obamacare.

“Healthcare reform’s going to be a big part of the agenda,” Johnson, speaking at a rally in Pennsylvania on Monday, told the crowd. “When I say we’re going to have a very aggressive first 100 days agenda, we got a lot of things still on the table.”

“No Obamacare?” one rally-goer asked Johnson, referring to the law Democrats passed in 2010, also known as the Affordable Care Act.

“No Obamacare,” Johnson replied, according to NBC News. “The ACA is so deeply ingrained, we need massive reform to make this work and we got a lot of ideas on how to do that.”

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Harris outpolls Trump on healthcare in battleground states, where it rates as the fourth-most important issue among voters, according to a Washington Post-Schar school poll, behind the economy, inflation and threats to democracy.

During the presidential TV debate in September, Trump said he had formed “the concepts of a plan” for replacing Obamacare.

The former president proposed a reform plan in the 2020 budget that said it supported “several initiatives to empower States and consumers to regain control over healthcare and increase affordability and consumer choice”. The plan incorporated a repeal of the ACA’s premium subsidies and Medicaid expansion, replacing them with a block grant to states, and would have capped federal spending on Medicaid. The plan could have reduced federal healthcare spending by more than $1tn over a decade.

In their election platform, Democrats argue that more than 20 million Americans have gained healthcare coverage and that the uninsured rate has been cut almost in half under Obamacare, including 2.3 million young adults. They note that healthcare discrimination based on pre-existing conditions is now illegal.

“Democrats have been fighting to secure universal health care for the American people for generations, and we are proud to be the party that passed Medicare, Medicaid, and the Affordable Care Act,” the policy statement reads.

A return to pre-Obamacare policies would mean a return to “free-market” healthcare that would harm healthcare safeguards for vulnerable sections of the population, Democrats argue.

“We want to take a blowtorch to the regulatory state,” Johnson reportedly said. “These agencies have been weaponized against the people, it’s crushing the free market; it’s like a boot on the neck of job creators and entrepreneurs and risk takers.”