The House Monday passed the first significant expansion of the Affordable Care Act since its birth a decade ago, providing Democrats a high-wattage platform to castigate President Trump for his efforts to overturn the landmark law during a pandemic and an election year.

The 234-179 vote, almost entirely along party lines, was a hollow exercise in terms of any chance the bill would become law and reshape federal health policy. Moments after the debate began, the White House announced the president would veto the legislation if it reached his desk, though a wall of Senate Republican opposition to the measure makes that a moot point.

Still, the vote was laden with political implications. Less than five months before presidential and congressional elections, it forced Republicans to go on the record about the ACA and showed anew the parties’ highly charged ideological differences on health care — an issue that consistently polls as a prime concern among U.S. voters. Democrats portrayed themselves as champions of access to affordable care at a critical time. Republicans characterized the opposing party as authors of a failed law and proponents of tax increases.

The Democrat-led House on June 29 passed a bill to expand the Affordable Care Act, allowing more people to qualify for coverage. (U.S. House of Representatives)

Historically, Democrats engender greater public trust than Republicans on their handling of the issue, and arguments that the GOP sought to deprive consumers of health care helped Democrats take the House majority two years ago.

Monday’s vote symbolized that House Democrats have a path to make health insurance and treatment more accessible at a moment when the novel coronavirus — and the jobs the pandemic has cost — has strained the U.S. health system, robbed millions of Americans of health benefits and caused nearly 125,000 deaths nationwide.

The legislation would add to some of the ACA’s central elements by expanding eligibility for insurance subsidies to those at higher incomes and pressuring more than a dozen states to expand Medicaid. It also would blunt some of the ways the Trump administration has watered down the law.

The hours of debate before the vote allowed Democrats to point out, again and again, that the Trump administration is seeking to invalidate the ACA in a lawsuit before the Supreme Court that was initiated by a group of Republican attorneys general who contend the entire law is unconstitutional.

“As lives are shattered by the coronavirus, the protections of the Affordable Care Act are more important now, more than ever,” said House Speaker Nancy Pelosi (D-Calif.). Noting that both Trump and congressional Republicans promise to preserve the law’s protections for people with preexisting medical conditions, she said: “Oh really? Then why are you in the United States Supreme Court to overturn them?”

Three years after a Republican Congress failed to pass a series of ACA repeal plans, House Majority Leader Steny H. Hoyer (D-Md.) accused Republicans of producing no substitute for the ACA.

Republicans, who have tried more than 70 times in the past decade to repeal the ACA or undercut it, cast the ACA as a failure in not making health care more affordable. The ACA is the “most unpopular health care plan in American history,” said Rep. Kevin Brady (R-Tex.), senior Republican on the House Ways and Means Committee.

Rep. Greg Walden (R-Ore.), the senior Republican on the House Energy and Commerce Committee, said the bill would put “a dagger in the heart of innovation” in treatments for diseases by allowing the government a stronger hand in negotiating drug prices — and would provide insurance subsidies to the wealthy.

Under the law, federal insurance marketplaces and similar state ones opened in 2014 for individuals and families who cannot get affordable health benefits through a job. The law provides federal subsidies for insurance premiums for those with incomes up to 400 percent of the federal poverty level — about $51,000 for an individual and nearly $105,000 for a family of four.

The bill would eliminate the 400 percent threshold, saying for the first time that no one would be required to pay more than 8.5 percent of their income on the most popular tier of marketplace health plans.

The legislation would place financial pressure on states that have not expanded Medicaid, the insurance program for low-income Americans run jointly by the federal government and states. The ACA originally expanded Medicaid nationwide, but a 2012 Supreme Court ruling, in which justices upheld the law’s constitutionality, gave each state the choice of whether to expand Medicaid.

For 14 states that have not expanded the program, the bill would reduce federal funding for traditional Medicaid. It would also add an inducement, paying for the entire initial cost of an expansion — as the law did when expansions first were allowed in 2014.

Medicaid also would guarantee that all women in the program would stay eligible for coverage for a year after they give birth — a step to address the nation’s high rates of medical problems and deaths among new mothers.

Among reversals of changes the administration has made to the ACA, the bill would undo a rule that allows skimpy insurance plans to be sold for up to 12 months, returning them to a three-month maximum.

It would provide $100 million a year for outreach and enrollment assistance to encourage consumers to sign up for ACA health plans — activities the administration has slashed.

The bill also includes a longtime Democratic goal of allowing federal health officials to negotiate the price of drugs under Medicare, the vast federal insurance program for older and disabled Americans. Trump used to support that idea but turned against it.

In its statement opposing the bill, the White House said the measure “attempts to exploit the coronavirus pandemic to resuscitate tired, partisan proposals” and would undermine drug development in a way that is “imprudent given the current focus on developing vaccines and therapeutics rapidly to help America and the world combat the coronavirus.”

Energy and Commerce Committee Chairman Frank Pallone Jr. (D-N.J.) countered the bill “is a commonsense, fiscally responsible one-two punch that uses the federal government’s savings from lowering prescription drug costs to lower health insurance costs for Americans.”