The nomination of Judge Amy Coney Barrett to the Supreme Court marks a chance for the GOP to secure a decisive 6-3 conservative majority and accomplish long-held priorities for years to come.
With her conservative voting record and a judicial philosophy calling for a strict interpretation of the Constitution, Barrett would likely move the court solidly to the right -- and potentially cast a deciding vote to overturn or restrict Roe v. Wade, which enshrined a woman's right to an abortion, and invalidate the Affordable Care Act. Barrett, though, is certain to be circumspect about her views on those cases during confirmation hearings set for next week.
The 'worst poker playing'
Some incumbents appear to be minimizing the implications of Barrett's addition to the court, arguing that even with six conservative justices -- three nominated by Trump -- the court might not always rule in favor of the GOP's core policy goals.
Sen. Joni Ernst, R-Iowa, who sits on the Judiciary Committee and is currently wrestling for her seat with Democrat Theresa Greenfield, suggested Roe would not be overturned with Barrett on the court. Two thirds of Americans believe the landmark decision should remain intact, according to a June CBS News poll.
"I think the likelihood of Roe v. Wade being overturned is very minimal," Ernst, who is trailing Greenfield slightly in recent polling, said at a debate last week. "I don't see that happening, truly. I don't see that happening. But what we can do is certainly educate the public on how important life is ... I'm adamantly pro-life. I will stand behind that."
In North Carolina, where Republican Thom Tillis is competing in a closely-watched contest with Cal Cunningham, a former Democratic state senator and Army veteran, the first-term senator contended that it's not certain how Barrett would vote on Roe if she were confirmed.
"I've heard my opponent talk about Justice Barrett will get on the bench and overturn Roe v. Wade," he said in the race's final debate Thursday night. "Nobody knows how she's going to rule on that."
Tillis, one of the two GOP members of the Judiciary Committee who contracted the virus, instead raised the possibility of chipping away at existing abortion rights -- potentially slowly eroding the breadth of the landmark Roe decision.
"What's likely to occur are cases that are going to go up to say, maybe we should improve standards for clinics that perform abortions," he said. "Maybe we should require doctors to have admitting privileges at a hospital nearby, in case the abortion goes bad. Maybe we should reconsider the extreme position that Cal Cunningham takes on partial birth abortion and on late-term abortions."
Even Trump sought to remove Roe as a campaign issue at the first presidential debate after Joe Biden, the Democratic presidential nominee, asserted that the decision is on the November ballot because of the Barrett confirmation fight.
"It’s not on the ballot," Trump said. "There’s nothing happening there. You don’t know her view on Roe v. Wade."
Last week, it surfaced that Barrett signed a 2006 newspaper ad by an anti-abortion group in which she said she opposed "abortion on demand" and defended "the right to life from fertilization to the end of natural life," the AP reported.
Both Iowa and North Carolina are battlegrounds in the race for the White House, too, with Trump and Biden neck-and-neck in both states.
But in reliably-red Montana, which voted for Trump by 20 points in 2016 and is known for its independence and split-ticket voters, Republican Sen. Steve Daines is fighting for his political life against Democratic Gov. Steve Bullock.
Pressed on what will happen to the 23 million Americans insured under the Affordable Care Act if the Supreme Court, which hears the Trump administration's challenge to President Barack Obama's signature legislative accomplishment on Nov. 10, strikes it down, Daines used a similar argument as Ernst and Tillis, but this time about the ACA.
Minutes after he said, "I support the nomination of Amy Coney Barrett, she's exactly the kind of justice I want to see on the Supreme Court," Daines asserted that the Supreme Court, even with the addition of Barrett, might not overturn the ACA.
"I've spoken to experts who are looking at this case. This is a very big case. It's going to go before the United States Supreme Court regarding the Affordable Care Act, better known as Obamacare," he said at a debate last week. "The experts are saying it's highly unlikely they'll overturn the ACA, that that's the consensus of many legal experts."
The three Senate campaigns did not respond to ABC News' request for comment on each candidate's characterization of Barrett’s potential impact on the court.
At a time when protecting both abortion rights and the health care law are popular, some Republican strategists are critical of the GOP's efforts in the final stretch of the election, suggesting it's misleading.
"I think it's the worst poker playing I've ever seen," said Jeff Timmer, a veteran GOP strategist and former executive director of the Michigan Republican Party, in an interview Friday. "They're bluffing...She has a clear paper trail on abortion...I mean, is Trump going to withdraw the lawsuit? It's ludicrous to say that it's not going to happen. That's the impetus for getting her confirmed ahead of time because it's politically dangerous for them to rush forward."
Trump's selection of Barrett late last month comes after he vowed in 2016 to only appoint judges who are "pro-life" and said that overruling the 1973 Supreme Court decision will "happen automatically." He's also made invalidating the ACA a core goal of his administration.
Barrett's hasty confirmation process is set to begin on Oct. 12, and proceed over four days before the Judiciary Committee. Even with Trump announcing he contracted COVID-19, and two members who sit on the committee sidelined after testing positive too, top GOP leaders said they are still charging forward as planned.
"Full steam ahead with the fair, thorough, timely process that the nominee, the Court, & the country deserve," Senate Majority Leader Mitch McConnell tweeted. Virtual attendance by infected members is allowed, but a majority of members must be "actually present" in order to vote on a nomination, according to panel rules. Barrett herself tested negative on Monday, a senior administration official told ABC News.
Despite the moves by some members of his own party, McConnell said on Thursday he believes Barrett's nomination will be "a big asset" in "states around the country."
The sudden injection of the Supreme Court into the election is not only a tightrope for endangered Republican senators, though, who will ultimately have to vote on her nomination if, and more likely when, one comes to the floor. It's also emerging as a complication for GOP challengers, too.
After recently appearing at a Trump rally in Freeland, Michigan, John James -- the Republican running to oust Sen. Gary Peters, one of two Democrats in a competitive race this cycle -- broke ranks with the president, telling a local ABC affiliate that he does not support the administration's lawsuit that will come before the Supreme Court without a replacement health care plan enacted.
"I do not believe that you should pull the rug out from under people, and I don't support this move without a plan in place," he said, without criticizing Trump. "We have to protect people with pre-existing conditions and keep our promises to our seniors. I don't think the ACA is perfect it needs improvement."
Trump and Republicans have yet to put forth a replacement plan for the ACA.
James' resistance to supporting the White House's efforts to dismantle the ACA entirely, Timmer said, is indicative of Republicans knowing "this is a losing political issue."
"He has the luxury of having cake and eating it too," he said. "He doesn't have to vote on Barrett...But the fact is that all this is going to happen regardless. Even if John James were to win, he doesn't have take a stand on any of this. And so he has the luxury of saying the politically safe position in the end."
For Democrats, it's all about health care
Democrats are leveraging the process to refocus the remaining weeks of the election as a referendum on protecting the ACA, an issue that landed them control of the House and is central to their strategy for winning back the presidency and the Senate. It's also emerged as key to their case against Barrett.
"Keep the argument very simple -- McConnell and Republicans are trying to rush through a confirmation of a justice who will overturn protections for preexisting conditions," a memo circulated by House Democrats' campaign arm outlines. "If McConnell and Republicans get their way, millions of Americans will lose healthcare coverage -- in the midst of a pandemic."
Late last week, Senate Minority Leader Chuck Schumer used a procedural maneuver to force a vote on blocking the Trump administration's support of the ACA lawsuit, which was mostly symbolic and put Republicans on the record about where they stand on the issue. Some of the most endangered GOP incumbents sided with Democrats, including Ernst, Colorado Sen. Cory Gardner, Maine Sen. Susan Collins, Arizona Sen. Martha McSally, and Alaska Sen. Dan Sullivan, in an apparent move to put distance between them and Trump's efforts to overturn the ACA.
Both Tillis and Daines toed their party line and voted against the measure.
Democrats are eager to highlight the GOP's tough position, as both the ACA and Roe cut against Republicans' top priorities, party strategists say.
"Senate Republicans are blatantly trying to deceive voters about their own records and the intended consequences of their rush to fill this Supreme Court vacancy with a nominee hostile to the Affordable Care Act and women’s reproductive rights," said Stewart Boss, a spokesperson for the Democratic Senatorial Campaign Committee, in a statement. "These vulnerable incumbents are racing to distance themselves from their own rigid positions because there’s an election around the corner and they know their anti-health care stances are harmful and out of touch with voters."
ABC News' Trish Turner, Meg Cunningham, Allison Pecorin and Katherine Faulders contributed to this report.