WASHINGTON (AP) — Democrats are zeroing in on health care as one of the few issues that might resonate among Americans who have largely shelved election year politics as they focus on protecting their families from the spreading coronavirus.

Joe Biden, the prospective Democratic nominee, is criticizing President Donald Trump for refusing to reopen "Obamacare" enrollment to allow more Americans to sign up for medical insurance during the crisis. Congressional candidates are slamming Republicans for not doing enough to protect access to health coverage. And on Capitol Hill, Democratic leaders are pushing for the next coronavirus response legislation.

Democrats were always going to focus on health care after the issue helped them retake control of the House in 2018. But the coronavirus pandemic has added new urgency to the push, sidelining other policy debates that dominated the Democratic primary, such as free college education or sweeping environmental reforms.

"It's definitely amplified to people who thought that it was not the overarching issue," said Betsy Londrigan Dirksen, the Democrat running against GOP Rep. Rodney Davis for an Illinois congressional seat. "Health care, and access to quality affordable care, is the No. 1 issue, and it will be on the ballot in November."

Democrats still hope to put Trump on defense on other issues, such as his handling of the economy and his overall leadership. But as hospitals struggle to cope with surging coronavirus cases, few issues may feel as tangible to voters as health care.

Trump and Vice President Mike Pence struggled to respond to questions during a press briefing this week about why the administration has refused to reopen healthcare.gov to allow all uninsured Americans to buy coverage through the government marketplace.

Pence noted that private insurers are waiving fees on testing and that states could expand coverage under Medicaid, but he didn't directly explain the administration's thinking about the exchanges. He later said the administration was considering direct aid to hospitals who treat uninsured patients suffering from COVID-19.

Biden called the resistance to reopening the exchanges "callous."

Trump has long pledged — and failed — to offer an alternative to Obamacare that would be cheaper and provide better coverage. Democrats are now highlighting the administration's support of a Republican-backed legal effort to invalidate the Affordable Care Act's individual mandate, which could ultimately dismantle the entire law. The Supreme Court is expected to hear arguments in the case this fall.

Guy Cecil, chair of Priorities USA, the biggest Democratic outside group, which is leading much of the Democratic opposition to Trump, said the group's polling has shown Democrats never lost their advantage on health care, but the coronavirus outbreak has brought it into sharp relief.

"The idea that, even in the midst of all of this, the president is still insistent on throwing our health care system into chaos I think is pretty telling," he said.

A handful of Democratic outside groups, including Cecil's, are spending millions of dollars attacking Trump's response to the pandemic, with everything from television to digital ads to efforts promoting news reports aimed at combating what they see as misinformation coming from the Trump administration about the outbreak.

Priorities USA has spent over $6 million on ads in four key general election states — Florida, Michigan, Pennsylvania and Wisconsin — that suggest Trump downplayed the severity of the crisis even as the number of infections rapidly climbed.

Democratic super PACs American Bridge and Pacronym have also invested big in coronavirus ads, and a pro-Biden super PAC put out its own ad contrasting Trump with past presidents who've confronted crises and charging the president "failed" in addressing this one. Protect Our Care, another outside group, began an ad campaign this week in midwestern states highlighting the shortage in supplies for front-line health care workers and the spike in unemployment resulting from the outbreak.

The pro-Trump super PAC America First Action responded with a $10 million ad campaign in Wisconsin, Pennsylvania and Michigan attacking Biden.

Trump campaign spokeswoman Kayleigh McEnany said the president is "indisputably the best person to lead our country on health care," pointing to his work to get health care industry executives to agree to offer free testing and expanded coverage for those suffering from the illness. She also argued that Trump has been working while in office to bring health care costs down for Americans.

Like most Americans, Biden is grounded at home, unable to campaign in a traditional manner or harness the media spotlight. He holds daily events related to the virus, including virtual roundtables featuring first responders and others acutely affected by the outbreak. He holds daily calls with an advisory board of medical doctors and experts, and is reaching out to a number of governors dealing with the crisis in their states.

There are still risks to focusing so much on health care. The Democratic primary exposed deep divides in the party over how to best expand access to affordable health insurance. Progressives, led by Sen. Bernie Sanders, insist on transitioning to a government-run system that replaces private coverage. Biden and other moderates oppose "Medicare for All."

"The idea it would have fundamentally changed anything is just not accurate," Biden told reporters on Thursday. "I don't see where Medicare for All would make any difference in terms of the speed with which, and the recovery rate which would occur if in fact it existed."

Republicans have already accused Democrats of politicizing a tragedy, and a number of Democratic operatives privately acknowledged they were concerned about striking the right balance. Biden insists he's not blaming Trump for the virus, but simply wants him to "move faster" with his response. Just this week, Biden aides said they were working to set up a call with Trump to discuss the coronavirus response.

Downballot candidates also are elevating arguments centering on health care.

In Texas, veteran and businesswoman MJ Hegar, who's challenging Republican Sen. John Cornyn, said health care has always been a top issue for voters. But she said the coronavirus underscored how out of touch politicians in Washington are to the realities confronting average Americans.

"He (Cornyn) doesn't understand how broken the health care system is because he's been on government-provided health care his whole career," she said. "You know, it's really highlighting to people the problem with having folks like him in office," she said.