By Arlette Saenz, Sarah Mucha and Tami Luhby, CNN

(CNN) -- Democratic presidential nominee Joe Biden intends to make a push on health care in the wake of Supreme Court Justice Ruth Bader Ginsburg's death as a political fight over the Supreme Court vacancy is already underway.

In the immediate days after Ginsburg's passing, the Biden campaign has not signaled a fundamental shift in its campaign strategy, which has hinged on the coronavirus pandemic and the economy, as President Donald Trump quickly moved to make the Supreme Court vacancy a central issue in his campaign.

Instead, Biden campaign officials say the former vice president plans to make defending the Affordable Care Act and its sweeping protections for pre-existing conditions a key focus, with an aide saying they view the President's efforts to dismantle Obamacare as a motivating issue for voters.

"Make no mistake: the fight to preserve protections for pre-existing conditions is on the ballot," a Biden campaign aide said.

Biden started that push with a speech in Philadelphia Sunday as he assailed Trump's support of a Republican-led challenge to the Affordable Care Act as the Supreme Court is scheduled to hear oral arguments on the case one week after the election.

"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, to strip away the peace of mind of more than 100 million Americans with pre-existing conditions," Biden said in a speech at the National Constitution Center.

Biden also repeated his call for the Senate not to consider a nominee until after voters have selected the president in this year's election.

"If Donald Trump wins the election, then the Senate should move on his selection and weigh the nominee he chooses fairly," Biden added. "But if I win this election, President Trump's nominee should be withdrawn, and as a new president, I should be the one who nominates Justice Ginsburg's successor."

Hours after learning of Ginsburg's death Friday, Biden insisted a replacement should not be named until after voters have chosen who will be president -- a position embraced by Senate Democrats.

"Let me be clear that the voters should pick the president and the president should pick the justice for the Senate to consider," Biden said in New Castle, Delaware, Friday night.

"This was the position of the Republican Senate took in 2016 when there were almost 10 months to go before the election," Biden said, a reference to the GOP-controlled Senate in 2016 blocking a hearing on then-President Barack Obama's Supreme Court nominee Merrick Garland in an election year. "That's the position the United States Senate must take today."

Biden's running mate, California Sen. Kamala Harris, sits on the Senate Judiciary Committee, which would hold any Supreme Court nomination hearing. She echoed Biden's sentiment in a fundraising e-mail on Saturday, saying, "The work of holding Senate Republicans accountable to the standard they set in 2016 starts now."

A Biden campaign aide told CNN that Biden, Harris and their staff have been in contact with Democratic leadership in the Senate and the House about the Supreme Court vacancy, adding that congressional Democrats and the campaign will be "regularly coordinating."

The aide also said they are aligned on the message on the need to protect the Affordable Care Act. "They are strongly unified in the belief that this fight underscores the stakes of the election more than ever -- especially when it comes to Americans' health care during the pandemic," said the aide.

At a campaign rally in North Carolina Saturday evening, Trump indicated he will choose a Supreme Court nominee "next week" and "it will be a woman." Senate Majority Leader Mitch McConnell has vowed to hold a Senate vote on the President's nominee but has not laid out a specific timetable.

"To jam this nomination through the Senate is just an exercise in raw political power and I don't believe the people of this nation will stand for it," Biden said Sunday.

"I appeal to those few Senate Republicans, the handful who really will decide what happens, please follow your conscience," Biden, a former chairman of the Senate Judiciary Committee, said. "Don't vote to confirm anyone nominated under the circumstances President Trump and Senator McConnell have created. Don't go there. Uphold your constitutional duty, your conscience. Let the people speak. Cool the flames that have been engulfing our country."

In the days since Ginsburg's death, the Trump campaign has ramped up its calls for Biden to release a list of possible Supreme Court justices as the President has done. Shortly before Ginsburg's death was announced, Biden indicated he would not release such a list before the election.

He elaborated on his decision not to release a Supreme Court list on Sunday, saying he would not want to create the appearance of influencing a "person's decision-making as a judge" if they were on a list. He also cautioned that any one on a list could become the subject of "unrelenting attacks" without the ability to defend themselves and said he would want to make his choice with bipartisan input from the Senate.

Biden has previously said he would name a black woman to the Supreme Court if he was elected and a Supreme Court vacancy occurred.

Biden thus far has also resisted some calls to add additional seats to the Supreme Court, a position embraced by some of his rivals during the Democratic primary. In an interview with an Iowa outlet last year, Biden said, "No, I'm not prepared to go on and try to pack the court, because we'll live to rue that day."

Battle over health care

Biden's upcoming health care push comes as the number of coronavirus deaths in the United States nears 200,000 and as the Supreme Court prepares to hear the Affordable Care Act case.

Biden stands solidly behind the Affordable Care Act's strong protections for those with pre-existing conditions, which bar insurers from denying coverage or charging higher premiums based on a person's medical history.

Trump has also repeatedly promised that he would maintain protections for those with pre-existing conditions. But his actions say otherwise. His administration asked the Supreme Court in June to invalidate the Affordable Care Act, which would wipe out the key provisions that protect those who are sick or have been in the past.

The case stems from a lawsuit brought by a coalition of Republican state attorneys general who argue that when Congress cut the tax penalty on the uninsured to zero, it rendered that individual mandate unconstitutional. The group also contends that the entire law should fall because the mandate was intertwined with a number of other provisions.

Trump's Justice Department has largely backed the Texas-led coalition, though it recently argued that the ruling should only apply to the 18 states that brought the challenge. The Supreme Court will hear oral arguments on November 10, one week after the presidential election.

Health care was also a key issue that helped propel Democrats to the House majority in the 2018 midterm elections, an approach the Biden campaign and its allies hope to replicate heading into November.

"People are more mindful than ever of the need for health insurance, health coverage, protection from the virus, the stresses on the health care system," Neera Tanden, the president and CEO of the Center for American Progress, said. "With the pandemic, these issues have become even more salient for people."

The Biden campaign has focused some of its TV ads on health care, including a pair of new battleground ads on the issue unveiled this week, as they've tried to tie the issue of health care to the pandemic.

Biden's plan seeks to expand health care coverage by making Affordable Care Act policies more affordable, particularly for middle class Americans who don't qualify for federal help buying plans. He would create a government-run insurance plan, known as the public option, which would provide the same broad coverage as the policies on the Obamacare exchanges.

The former vice president also would expand the federal subsidies offered on the Affordable Care Act exchange policies so that no one would have to pay more than 8.5% of their income toward monthly premiums. And Biden would automatically enroll uninsured, low-income Americans either in the public option or in Medicaid, depending on whether their state expanded Medicaid.

In a concession to the party's progressive wing, Biden proposed lowering the Medicare eligibility age to 60, instead of 65. He also has proposed an array of measures aimed at reducing prescription drug costs, including allowing Medicare to negotiate prices and letting consumers buy medication from other countries.

Still, Biden's plan would not cover everyone. The campaign estimated it would insure 97% of Americans, though this was before he proposed reducing the Medicare eligibility age.

Trump has long promised to unveil a plan to replace the Affordable Care Act -- including at a town hall last week -- but has yet to issue a comprehensive proposal.

Instead, the President and his administration have put forth a series of smaller measures that officials and the campaign point to as his health care efforts, though many remain in the proposal stage. They seek to increase the transparency of hospital prices, combat opioid addiction, improve kidney health and make Medicare Advantage plans more attractive, among others.

In recent weeks, he issued four executive orders that largely recycle previous proposals aimed at reducing drug costs, including allowing the importation of drugs from Canada and tying prices of certain Medicare drugs to their cost in other countries.

One Trump health care executive order that has gone into effect: The expansion of short-term health plans, which do not have to adhere to Obamacare's protections for those with pre-existing conditions.

This story has been updated with Biden's remarks in Philadelphia and comments from a Biden campaign aide.