Republicans searching for that elusive issue to erase the Democrats’ critical edge in voter enthusiasm heading into the midterm elections believe they’ve found their golden ticket in the retirement of Supreme Court Justice Anthony Kennedy.

Senior Republicans are predicting that the opportunity to replace Kennedy, a swing vote on the narrowly divided high court, with a young conservative who could tilt the court to the right and serve for decades, will galvanize the conservative base and motivate rank-and-file GOP voters to put any uneasiness with President Trump aside and stick with the party in November.

[Here are the 25 possible candidates to replace Kennedy]

“This is every Democrat candidate’s worst nightmare, as it changes the game on turnout,” Republican pollster Chris Wilson told the Washington Examiner on Wednesday. “It doesn’t just close the enthusiasm gap, it injects rocket fuel into the evangelical base that helped Trump win swing states.”

The midterm elections have shaped up as a backlash against Trump, threatening Republican majorities in the House and Senate.

Energy on the Democratic side needs no explanation — the Left is motivated to register a vote against the president. Republicans are experiencing the drag on turnout that typically accompanies winning the White House, as GOP voters, exhausted by the Trump’s provocative behavior, eye Democratic alternatives and grass-roots conservatives disappointed with Congress consider staying home.

Republicans are struggling to mitigate midterm election headwinds amid ongoing gusts from the White House — on immigration, trade, the Russia investigation, and Trump’s proclivity to discuss it all on Twitter. They see the debate over a Supreme Court nominee as the great equalizer with a Democratic base already as electrified as it could possibly get.

“One thing that energizes conservatives more than anything else is the Supreme Court,” Senate Majority Whip John Cornyn, R-Texas, said.

Republicans were already poised to pad their 51-49 Senate majority. The party benefits from a favorable map that features 10 seats up in states Trump won in 2016.

But Republicans say a monthslong battle over Kennedy’s replacement, and expected confirmation vote just before the election, is an insurance policy of “immeasurable” value. It gives the Republicans a tangible issue to motivate low-propensity voters and put the squeeze on vulnerable red state Senate Democrats who must choose: vote with their state or anger the liberal base.

Democratic operatives concede that it’s a dilemma for the party’s Senate incumbents that could sow division and prove costly in November. Democratic leaders and influential progressives are already demanding the confirmation of Trump’s forthcoming nominee be delayed until after the midterm elections, similar to Senate Majority Leader Mitch McConnell's blockade of a vacant Supreme Court seat prior to 2016.

“The needle just moved from a plus-two Democratic advantage to a plus-three GOP environment. Those five points could well equal a gain of five Senate seats,” said Jeff Roe, a GOP strategist active in Senate races, including on behalf of state auditor Matt Rosendale, the Republican challenging Democratic Sen. Jon Tester in Montana.

After conservative Supreme Court Justice Antonin Scalia died in February 2016, McConnell, R-Ky., announced he would not hold hearings or consider a replacement appointed by outgoing President Barack Obama. McConnell argued it would be improper to install a new justice months before a presidential election, that the voters should weigh in and the decision left to Obama’s successor.

Democrats cried foul, but McConnell refused to budge, and the issue ultimately paid dividends for Trump.

His promise to appoint a justice in the mold of Scalia made the difference with wavering Republicans hesitant to support ideological unreliable populist and propelled him to the White House. Trump’s high court pick, Justice Neil Gorsuch, has been a source of comfort for many Republicans when other aspects of his leadership left them questioning their 2016 vote.

The House doesn’t participate in the confirmation process, and Kennedy’s replacement is to be confirmed before Election Day.

But Republicans are optimistic the Supreme Court could alter a political atmosphere dominated by Trump’s indiscretions and turn the midterm elections into a referendum on partisan control of Congress that the GOP can win. The issue, they say, could drive Republicans to the polls in battleground House districts to vote for Republicans, even in states without competitive Senate contests.

“I’m sorry to see Justice Kennedy go. But he probably picked the moment that was opportune, politically, for Republicans,” Rep. Tom Cole, R-Okla., said.

Al Weaver contributed to this report.