PHILADELPHIA — Joe Biden on Sun­day used the sud­den Supreme Court vacan­cy to rein­force his argu­ment that the upcom­ing elec­tion should be a ref­er­en­dum on Pres­i­dent Don­ald Trump’s han­dling of health care and the coronavirus.

The death of Jus­tice Ruth Bad­er Gins­burg jolt­ed the pres­i­den­tial cam­paign just six weeks before the elec­tion and as sev­er­al states are already vot­ing. Trump has seized on the oppor­tu­ni­ty to nom­i­nate a new jus­tice to moti­vate his most loy­al vot­ers. Biden kept the focus on health care, which has proven to be a win­ning issue for Democ­rats dur­ing pre­vi­ous elec­tions and could be even more res­o­nant amid the pandemic.

The Supreme Court will hear a Repub­li­can-led case chal­leng­ing the Afford­able Care Act, which the Trump admin­is­tra­tion sup­ports, the week after the Nov. 3 elec­tion. Biden charged that Trump is seek­ing to under­mine the pro­tec­tions for peo­ple with pre-exist­ing con­di­tions under the ACA, as well as its pro­vi­sions cov­er­ing pre­ven­ta­tive care for women.

“Mil­lions Amer­i­cans are vot­ing because they know their health care hangs in the bal­ance,” Biden said dur­ing remarks at Con­sti­tu­tion Cen­ter in Philadel­phia. “In the mid­dle of the worst glob­al health cri­sis in liv­ing mem­o­ry, Don­ald Trump is before the Supreme Court, try­ing to strip health care cov­er­age away from tens of mil­lions of families.”

The Supreme Court could also hear cas­es on a few more par­tic­u­lar­ly salient issue in the next few months: vot­ing rights, and poten­tial­ly who wins the Novem­ber election.

Biden is expect­ed to focus in the weeks ahead on the Demo­c­ra­t­ic fight to pre­vent a nom­i­nee from being con­firmed to the court, with a par­tic­u­lar empha­sis on the effect the court could have on health care and cli­mate change. Biden aides stopped short of rul­ing out the pos­si­bil­i­ty the cam­paign would adver­tise around the court fight, though that deci­sion hadn’t been finalized.

Trump is promis­ing to put forth a nom­i­nee this com­ing week and Sen­ate Major­i­ty Leader Mitch McConnell, R‑Ky., has vowed to call a vote.

“In a raw polit­i­cal move, this pres­i­dent and the Repub­li­can leader have decid­ed to jam a life­time appoint­ment to the Supreme Court through the Unit­ed States Sen­ate,” Biden said. “That’s the last thing we need at this moment.”

Biden is still not, how­ev­er, plan­ning to release a list of poten­tial Supreme Court nom­i­nees, because putting out a full list, the aide said, would fur­ther the court and the nom­i­na­tion process, aides said. Biden’s aides said those inter­est­ed in his think­ing on a jus­tice can look to his long his­to­ry as chair­man of the Sen­ate Judi­cia­ry Com­mit­tee for guidance.

Their refusal to put names to Biden’s poten­tial court pick under­scores the polit­i­cal per­il that the Supreme Court debate holds for Biden. Con­ser­v­a­tives are still ener­gized by the issue, and putting out names could offer Trump and his allies a list of con­ser­v­a­tive boogey­men to use against Biden to rev up his base.

Trump him­self, at a ral­ly Sat­ur­day night, basked in chants of “fill that seat” from the audi­ence, and has pledged to move quick­ly on the nom­i­na­tion, whom he says is like­ly to be a woman.

Indeed, the Supreme Court has tra­di­tion­al­ly been seen as a major moti­va­tor for con­ser­v­a­tive vot­ers, for its sig­nif­i­cance to hot-but­ton social issues like gay rights and abor­tion. But in recent years, fol­low­ing the con­tentious con­fir­ma­tion fight over Supreme Court Jus­tice Brett Kavanaugh and a num­ber of high-pro­file rul­ings on the Afford­able Care Act, polls sug­gest the issue is becom­ing more salient for Democrats.

A Pew Research Cen­ter poll con­duct­ed in August sug­gest­ed a com­pa­ra­ble num­ber of Biden and Trump vot­ers view the appoint­ment of Supreme Court jus­tices as “very impor­tant” to their vote.

While Biden’s aides acknowl­edge that the issue is still sig­nif­i­cant for con­ser­v­a­tives, they believe it could be a win­ning one for their cam­paign, poten­tial­ly dri­ving sup­port among unde­cid­ed mod­er­ates, young vot­ers and women, who may be ener­gized in par­tic­u­lar by the con­tin­ued legal attacks on abor­tion rights.

They point to the mas­sive fundrais­ing num­bers seen for Democ­rats online — $91.4 mil­lion processed through Demo­c­ra­t­ic fundrais­ing engine Act­Blue from Fri­day night through Sat­ur­day — as fur­ther evi­dence of the base enthu­si­asm around the issue.

“So, I think in that sense, the vacan­cy will real­ly sharp­en the focus on the stakes in this elec­tion when it comes to life and death and the health of Amer­i­cans,” Sen. Tim Kaine, a Vir­ginia Demo­c­rat who was Hillary Clinton’s run­ning mate in 2016, said Sunday.