President Barack Obama’s successor could have the chance to orchestrate the biggest re-make of the Supreme Court’s composition in four decades, further raising the stakes of the 2016 election cycle.

Justice Antonin Scalia’s death gives Obama a chance, though potentially slim, to replace a solidly conservative vote with a consistently liberal one. But, with three justices beyond or approaching their 80th birthdays, voters in November will get a chance to make clear in which political direction they prefer the high court to lean for decades to come.

“You’ve already got one octogenarian on the court, with another coming soon — and you’ll have a third in the not-so-distant future,” said Stephen Vladeck of American University’s Washington College of Law. “So there’s no question — especially if the next president wins two terms — that the next administration will have a chance to really change the court’s make up.”

Obama on Supreme Court Nomination: ‘The Constitution is Clear’

Justice Ruth Bader Ginsburg is 82, and will turn 83 on March 15. Justice Anthony Kennedy is 79, but will turn 80 on March 11. And Justice Stephen Breyer is 77.

The average American lifespan is currently around 79 years, according to the Centers for Disease Control and Prevention’s National Center for Health Statistics.

That means, as Vladeck put it, “simple averages and actuarial tables tell us the court is about to undergo substantial changes.”

Scalia’s death at age 79 on Saturday at a luxury hunting resort in West Texas has put a conservative seat in play.

Should Kennedy die or decide to retire during the next president’s term, it would remove from the bench its so-called swing voter because the Ronald Reagan appointee sometimes crosses the ideological divide and votes with liberal justices.

And if Ginsburg or Breyer leave the court, the liberal bloc would lose reliable votes.

Because the next chief executive could end up appointing so many justices, and because he or she would be inclined to choose multiple justices of their ideology for the highest court in the land, the 2016 election cycle could be seismic.

“The presidential election will determine whether the court leans left or right,” said Kermit Roosevelt, a professor of constitutional law at the University of Pennsylvania. “The handful of close Senate races will determine the [ideological] range in which the next president can operate in selecting nominees.”

Should enough justices of a single ideological ilk vacate their seats, the next president would have a rare opportunity to build a solidly conservative or liberal Supreme Court — assuming the Senate confirms their nominees, that is.

Senate Majority Leader Mitch McConnell, R-Ky., wasted little time Saturday saying the next president should pick Scalia’s replacement. Obama fired back that he intends to send the Senate a nominee, and expects that individual to get a confirmation hearing and floor vote.

But Senate Republicans in tight re-election fights, including Kelly Ayotte of New Hampshire and Rob Portman of Ohio, are backing their majority leader.

“One of the challenges Republicans have had is putting together policies that differentiate Republicans from Democrats,” Dan Holler of the conservative Heritage Action group said Tuesday. He added that new Speaker Paul D. Ryan, R-Wis., is trying to do just that.

“There is no greater contrast that’s easy to explain than who should go on the Supreme Court,” Holler said. “It’s very clarifying — and very polarizing because it’s so important.”

Heritage Action does not engage directly in elections, but the organization does try to influence lawmakers on policy matters. It will seek to do just that in trying to convince more Senate Republicans to stand with McConnell, which would prevent Obama from replacing Scalia’s conservative vote with a liberal one.

“We’ll try and reinforce” that message to other GOP senators as Obama prepares to submit a nominee, and “help them stay strong” during the election cycle, Holler said.

And, from Republicans’ perspective, that’s for good reason.

That’s because should self-described democratic socialist Sen. Bernard Sanders, I-Vt., or self-described progressive Hillary Clinton win the Democratic nomination, “it would be an earthquake,” Roosevelt said.

He envisions a President Sanders nominating “very liberal justices” to replace Scalia and, under one scenario, the conservative swing voter Kennedy. Such nominees might breeze through Senate confirmation processes if a Sanders win was accompanied by “a Democratic populist wave that gives them the Senate,” Roosevelt added.

And Vladeck sees Clinton appointing “solid, center-left justices” while also trying to “bring some diversity to the court” in terms of religious beliefs, geographic location and which law school they attended.

On the flip side, Ted Cruz, the Texas freshman senator running second to Donald Trump in the Republican presidential primary, would “very clearly like a court filled with Scalias,” Vladeck said.

And what about Trump? Legal experts say that’s harder to predict, but they note his choices would have to hew conservative so the billionaire businessman could appease his political base.

“I’ll be interested to see whether Democrats can get their base as excited about Supreme Court appointments as Republicans seem to (be),” Roosevelt said. “I don’t think the American people have thought a lot about this. Scalia’s death gives them a chance to think long and hard about it.”

Contact Bennett at johnbennett@cqrollcall.com and follow him on Twitter at @BennettJohnT.

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