If the bare-knuckles partisan fight over the Supreme Court results in a triumphant President Trump adding a third justice to the bench, three areas seem especially ripe for change: abortion, gun control and religious liberty concerns important to the right.

But there’s another issue that might become a casualty: the court’s image, smudged as it may already be, as being above the nation’s political fray.

Republicans seem likely to prevail in this round. Trump said he will announce on Saturday his choice to replace the late liberal Justice Ruth Bader Ginsburg. Republican senators continue to fall in line, some reversing the positions they took when President Barack Obama in 2016 offered Judge Merrick Garland for an open seat in a presidential election year.

But the Republican show of strength could prompt a backlash if Democrats win the White House and flip the Senate in November. Many have promised retaliation, perhaps by expanding the court and erasing the conservative advantage.

All of which puts the justices on a political battlefield they try hard to avoid.

“The nomination battle is a huge threat to the court,” said Richard Lazarus, a Harvard law professor who closely studies the justices. “The chief justice and most of the associate justices believe strongly in the court’s image as a nonpartisan institution. But it is a battle they will lose if the other two branches insist on making the court into a partisan political institution.”

Despite blocking President Barack Obama's Supreme Court pick in 2016, some Senate Republicans have said they would fill such a vacancy in 2020. (The Washington Post)

Last term, there were indications the justices took pains to blur the reality that all five of the court’s conservatives were nominated by Republican presidents and the four liberals by Democrats.

Trump’s nominees to the court, Justices Neil M. Gorsuch and Brett M. Kavanaugh, were part of a 7-to-2 majority rejecting Trump’s objections to subpoenas for his personal financial records as part of investigations by a New York prosecutor and congressional committees.

Chief Justice John G. Roberts Jr., who has rigorously defended his colleagues and federal judges as nonpartisan, decided to stand behind a court precedent and joined liberals in rejecting a restrictive abortion law in Louisiana. It was the first time he has voted against an abortion regulation.

Liberal justices Stephen G. Breyer and Elena Kagan sided with conservatives in giving religious organizations more leeway in hiring and firing decisions.

The mix of outcomes was not reassuring to partisans on either side. Vice President Pence called Roberts a “disappointment,” and Trump said the court’s performance proved he needed more time to nominate more conservatives.

But the public seemed pleased. An annual Gallup poll showed the court’s approval at 58 percent, far better than that of the executive branch or Congress. It was the court’s best mark since 2009.

Moreover, the performance tempered calls for restructuring, such as increasing the number of justices.

The battle over Ginsburg’s replacement has reactivated the activists.

Democratic presidential nominee Joe Biden remains opposed to calls for reshaping the court. But Senate Minority Leader Charles E. Schumer (D-N.Y.) said after a meeting with his caucus that “everything is on the table.”

Typical was a tweet from Rep. Joe Kennedy (D-Mass.): “If he holds a vote in 2020, we pack the court in 2021. It’s that simple.”

Kennedy was referring to Senate Majority Leader Mitch McConnell (R-Ky.), who accused Democrats of “hysteria.”

“I’ll tell you what really could threaten our system of government — it’s not Senate Republicans doing legitimate things squarely within the Senate rules and within the Constitution the Democrats happen to dislike,” McConnell said. “No, what could really threaten our system is if one of our two major parties continues to pretend the whole system is automatically illegitimate whenever they lose.”

Mike Davis, who heads the Article III Project that advocates for Trump’s judicial selections, said the Republican Party is ready for a fight.

He said in a tweet that Trump “will transform the 5-4 John Roberts Court to the 6-3 Clarence Thomas Court. And he will get 3 or more Supreme Court picks in his 2nd term — along with flipping every circuit court. Because we’re still not tired of winning.”

The chances for Republicans to prevail in the fight over Ginsburg’s replacement improved markedly Tuesday, when Sen. Mitt Romney (R-Utah) announced his support for moving ahead with a nomination.

“My liberal friends have over many decades gotten very used to the idea of having a liberal court, but that’s not written in the stars,” he said.

In fact, the Supreme Court has not had a liberal majority since the Warren Court. Since 1969, Republican presidents have named 14 justices to the high court, compared with four from Democrats.

But some of those Republican appointees became more liberal over the years, and conservatives have been unhappy with the pace of change.

A court that has six conservatives could force Roberts to change his incremental tendencies.

Both Gorsuch and Kavanaugh already have joined Thomas and Justice Samuel A. Alito Jr. in expressing impatience with the court’s previous rulings on abortion.

All have called for reexamining some of the court’s decisions involving strict boundaries between government and religious organizations, and have said it is time for the court to examine whether state and local gun-control laws violate Second Amendment rights.

It would be likely that Trump’s new choice will share those concerns. Those familiar with the deliberations say two judges the president elevated to the appeals courts — Amy Coney Barrett and Barbara Lagoa — are the top choices.

Barrett has more of a record on the issues important to legal conservatives.

Sen. Josh Hawley (R-Mo.), who has made mistrust of Roe v. Wade essential to his support of a candidate, said Barrett meets the test.

On the U.S. Court of Appeals for the 7th Circuit, she joined a dissent about a ruling that found unconstitutional an Indiana law banning abortions sought because of the sex or disability of a fetus. The panel ruled, as it said other courts have, that Supreme Court precedent did not allow questioning of a woman’s reasoning for an abortion before viability.

Judge Frank H. Easterbrook, joined by Barrett and two other judges, reached out to disagree, even though the state had not appealed the panel’s decision on that part of the law to the full court.

Four of the Supreme Court’s conservatives — Thomas, Alito, Gorsuch and Kavanaugh — have at one time or another questioned the court’s reluctance to review lower-court rulings upholding state and local gun-control measures. Only Roberts, among the conservatives, has not.

When the court passed up a number of cases this year brought by gun-rights groups, Thomas objected. He wrote that his colleagues had prolonged a “decade-long failure to protect the Second Amendment” after the landmark 2008 decision in District of Columbia v. Heller finding an individual’s right to gun ownership.

Barrett might be on the same wavelength. She dissented from a panel that upheld the government’s right to withhold a gun permit from a felon, who she said had served his sentence and did not pose a danger.

“History is consistent with common sense: it demonstrates that legislatures have the power to prohibit dangerous people from possessing guns,” she wrote. “But that power extends only to people who are dangerous. Founding-era legislatures did not strip felons of the right to bear arms simply because of their status as felons.”

The court this term ruled that Title VII of the Civil Rights Act protected LGBTQ workers from discrimination, a decision in which Gorsuch and Roberts joined the liberals. But they left open the question of whether religious employers must comply.

“How these doctrines protecting religious liberty interact with Title VII are questions for future cases,” Gorsuch wrote.

And there is no shortage as the legal lines between religious rights and expanded protection for LGBTQ citizens are established.

Mark Rienzi, president of the Becket Fund for Religious Liberty, said he didn’t think the addition of a new justice changes much, because the decisions of the court on the issues his organization brings are not “5-to-4 nail-biters.”

But Paul D. Clement, a former solicitor general for President George W. Bush, said an expanded majority sometimes makes a difference. Speaking Tuesday at a Supreme Court preview session at Georgetown Law Center, he said, “You could get five justices who want to move the needle very quickly in this area.”