The message will only intensify in coming weeks, in light of Friday's death of Justice Ruth Bader Ginsburg. Her death leaves the decision in the high-stakes Trump-backed lawsuit to ax the entire ACA in the hands of an evenly-divided court where Chief Justice John Roberts was widely viewed to emerge as the key swing vote.

With the case coming up just one week after the election, Obamacare looks more vulnerable than ever before.

Voters’ worries about cost and coverage, and the responses from Biden and Trump, highlight how even amid the pandemic and its economic fallout, the nation’s troubled health care system remains a dominant force in U.S. politics. Regardless of who wins, the next president has the opportunity to reshape Obamacare, particularly for people who get their insurance on the individual market instead of through a job.

Democrats want more subsidies to get more people robust coverage in the Obamacare market, where costly premiums remain a deterrent and deductibles are also high. Biden is also promising a public option as a potentially cheaper alternative, although that’s a much heftier lift. Republicans want to keep chipping away at it by offering alternatives that are cheaper — but also have skimpier benefits.

Obamacare hasn’t solved health care cost problems; many voters believe the law made them worse. The Democrats paid dearly for the ACA’s early upheaval. But the politics have flipped. Now the law is more popular than ever and Republicans are the ones playing defense, trying to convince the public of their bona fides when it comes to protecting people with diseases like cancer or diabetes after a 2017 attempt to repeal Obamacare.

Trump has tried to claim the ACA’s most popular elements — particularly the preexisting conditions coverage protection — as his own. In fact, he and GOP lawmakers repeatedly tried and failed to repeal Obamacare, and Trump is now backing a legal effort to kill the law that goes to the Supreme Court precisely one week after the Nov. 3 election. And Trump is still struggling to articulate details of his often-promised, never-seen Obamacare replacement health plan.

A voter suffering from an expensive chronic condition challenged Trump at his televised town hall on Tuesday, asking him what he’d do to protect her coverage. Trump said he wouldn’t “hurt anything having to do with pre-existing conditions,” though his efforts to eliminate the law at the Supreme Court would do just that.

He also argued when moderator George Stephanopoulos pressed him that his administration has run the ACA better than Obama officials did, and he touted the elimination of the law’s unpopular penalty for people who don’t have insurance. The exchanges where individuals can buy insurance have stabilized in the last few years, with more insurers returning to offer plans. Trump also dismissed Obamacare as “a failure from day one” and claimed his not-yet-released alternative would better protect pre-existing conditions.

“We’re going to have a very good health care. I think maybe a great health care for less money,” Trump said. He didn’t give a date or details for a new health care plan he touted as “all ready.”

Trump has insisted for two years that his new plan is imminent. Congressional Republicans have shied away from making any such promise since their attempts to repeal the law failed in 2017.

Biden, at his own drive-in town hall on Thursday, likewise fielded worried questions from voters concerned about the fate of their health coverage. He talked about the ACA’s protections for pre-existing conditions in personal terms as he described his late son Beau Biden’s battle with cancer.

Biden also said he would “make sure that we reinstate the Affordable Care Act,” although he didn’t make clear exactly what he meant, since the law is still in effect. Trump has weakened it, partly by allowing people to get alternative health plans that are cheaper but with skimpy benefits that don’t meet Obamacare standards.

The presidential candidates’ rhetoric echoes the Obamacare messaging battle that’s raged across battleground districts for months. Democrats won the House in 2018 in large part because of their defense of the ACA, and this year they are replicating and updating that winning strategy for 2020.

Internal polling from the Democratic House campaign arm shows that defending coverage of pre-existing conditions is their most promising message in conservative-leaning competitive districts, including 41 districts that went for Trump in 2016. As an overall economic message, angst over high health costs also deeply resonates with voters, running a very close second to worry over small businesses trying to weather the pandemic-driven recession.

Both the Democratic Congressional Campaign Committee and Democratically-aligned outside groups are paying for TV ads focused on health care in nearly all their top targeted districts, especially red-leaning suburbs they’re trying to flip.

Republicans in close congressional races are staying largely quiet on Obamacare and pre-existing conditions, with memories still fresh of their party’s deep losses in the 2018 midterms. But a handful are on the defensive — running ads echoing Trump’s claims that the GOP will protect people with pre-existing conditions with or without the ACA and putting a personal spin on their promises.

Colorado Sen. Cory Gardner aired a TV spot this week featuring his mother, a cancer survivor, praising her son for “guarantee[ing] coverage to people with pre existing conditions forever — no matter what happens to Obamacare.”

Gardner and other incumbent senators in tight races voted to repeal the ACA without a GOP alternative that would have paralleled those protections — something they don’t mention in their ads.

Additionally, the bill Gardner is referring to is just one page, and experts say it would not prevent insurers denying coverage to people with serious health conditions or guarantee a set of minimum health benefits should the ACA fall in court.

Ads from other vulnerable Senate Republicans who voted to repeal Obamacare without a clear replacement include similar testimonials based on their family experiences.

In one of Georgia Sen. David Perdue’s ads that ran in August, his sister talked about surviving cancer and touted Perdue’s belief that “health insurance should always cover pre-existing conditions for anyone, period.” She added: “Anyone who says otherwise doesn't know my big brother's heart.”

In a recent spot for Sen. Martha McSally (R-Ariz.), a brain cancer survivor, says: “She's fighting for what's right when it comes to pre-existing conditions and making sure everybody has access to health care.”

Biden’s plan to expand the law with a public option is creeping into campaign messaging even for Democratic challengers in conservative states. Back in when Congress was considering the ACA in 2009, the public option was considered too radical to enact. Now it’s become the Democratic plan to build on Obamacare, a mainstream alternative to the government-run Medicare for all favored by the Bernie Sanders progressive wing.

“People also know how health care costs have gone up over years, and they are concerned about maintaining lower costs — which is why people are looking at a public option,” said Jill Schupp, a Missouri state senator who’s running against Rep. Ann Wagner (R-Mo.).

Schupp said she’s not shying away from talking about the public option and that the messaging is resonating with voters — particularly as so many people are unemployed. Missouri recently voted to expand Medicaid under the ACA.

There’s no full picture yet of how well Obamacare’s private health insurance exchanges have acted as a safety net during the pandemic as millions of Americans lost their jobs and their insurance. New analysis of U.S. Census Bureau data shows that the individual market hasn’t changed much — and health plans worry they could even see a shrinkage during November’s open enrollment period if people can’t afford Obamacare’s high-deductible coverage.

Biden, even as he touted the ACA’s patient protections for coverage, raised the public option as a priority addition to Obamacare, so that “nobody, nobody in the United States of America would go without being able to get covered for what they need.”