Republicans are facing a growing unity problem that's impeding their policy goals, even though they're in the majority. (Jenny Starrs/TWP)

The next Republican revolution began last week on a bright blue bus parked at a nighttime rally in Montgomery, Ala., days before a firebrand GOP candidate won the state’s Senate primary.

But unlike previous Republican revolutionaries, the hard-line figures who stepped out to cheers did not want to yank the party to the right on age-old issues such as taxes or spending. They wanted to gut it and leave its establishment smashed.

Fury infused these insurgents’ raw remarks as did a common theme: The Republican Party has failed its voters, and a national cleansing is needed in the coming year, regardless of whether President Trump is on board.

Longtime Republicans see a charged civil war on the horizon.

“There is an emotional component,” former House speaker Newt Gingrich (R) said of the frustrations of Trump’s core backers, who have grown increasingly vocal. “They want someone to kick over the table. And my advice to every Republican is: You better have an edge, or you become the problem.”

Controversial conservative and former Alabama chief justice Roy Moore won the Republican primary for the state's Senate seat on Sept. 26, setting up a crisis within the GOP. Here's a look at three problems his win poses for the D.C. establishment. (Jenny Starrs/The Washington Post)

That populist rage in the base as Trump struggles to enact his priorities — which lifted former judge Roy Moore to victory on Tuesday against Trump’s ally, Sen. Luther Strange (R-Ala.) — now threatens to upend GOP incumbents in 2018 as the latest incarnation of Republican grievance takes hold.

Stoked by former White House chief strategist Stephen K. Bannon and his incendiary media platform, Breitbart News, a new wave of anti-establishment activists and contenders is emerging to plot a political insurrection that is with Trump in spirit but entirely out of his — or anyone’s — control.

Central command is the “Breitbart Embassy,” a Capitol Hill townhouse where Bannon has recently huddled with candidates, from House prospects to Senate primary recruits. Hedge fund executive Robert Mercer and his daughter Rebekah — Bannon’s wealthy allies — have already pledged millions to the cause, said people briefed on their plans.

In the last seven years, the Mercers have emerged as some of the biggest political donors on the right, plowing tens of millions into GOP committees and super PACs. Their money has gone both to shore up the national Republican Party and to finance outside groups taking on the Washington establishment.

So far this year, the Mercers have contributed $2.7 million to federal political committees and campaigns, finance filings show.

Beyond cash, Mercer and Bannon also offer GOP rebels a vast media and advocacy ecosystem that generates attention on social media as well as small-dollar donations. Run by Rebekah, the Mercer family foundation has given $50 million to conservative and free-market think tanks and policy groups from 2009 to 2015, according to tax records compiled by The Washington Post and GuideStar USA, which reports on nonprofit companies.

Former Alabama chief justice Roy Moore. (Brynn Anderson/Associated Press)

And that blue bus — sponsored by the Great America Alliance and carrying former Alaska governor Sarah Palin, among other conservative celebrities, across Alabama — is scheduling stops across the country.

“If you don’t do your job, you’re going to see the bus, and you’re going to get bounced,” said Ed Rollins, the group’s strategist.

Rollins and Eric L. Beach, another adviser to the advocacy group, insisted that money would not save their elected Republican targets, pointing out that in Alabama they spent about $200,000, compared with the more than $10 million spent by the national GOP and Strange-aligned groups.

Mississippi state Sen. Chris McDaniel — who traveled to Alabama to meet with Bannon and is considering challenging Sen. Roger Wicker (R-Miss.) next year — called Moore’s success “inspiring” and said he is moving closer to launching a campaign fueled by the “establishment’s betrayal.”

“The environment feels so much better — people are so much more fed up than they were in 2014,” McDaniel said, referring to the year he nearly beat Sen. Thad Cochran (R-Miss.) in a Senate primary race.

The rumblings of an uprising come days after Senate Republicans shelved the party’s latest health-care proposal and as GOP lawmakers are inching forward on a proposal to cut taxes, but far from bringing legislation to a vote.

“Every Republican member of Congress is sitting there saying, ‘s---, this could happen to me,’ ” Rollins said.

Many players from the tea party era have returned to the breach: Palin, Bannon, Fox News personality Sean Hannity, talk-radio host Laura Ingraham and a cast of familiar foils who have long haunted House Speaker Paul D. Ryan (R-Wis.) and Senate Majority Leader Mitch McConnell (R-Ky.).

Their enemies, however, go beyond those Republican leaders — anyone remotely linked to them is at risk of attack.

“You are going to see, in state after state after state, people that follow the model of Judge Moore, that do not have to raise money from the elites, the crony capitalists, from the fat cats in Washington, D.C., New York City and Silicon Valley,” Bannon told Moore’s supporters on Tuesday.

Bannon added that Moore’s upset of Strange was “starting a revolution” that would either topple GOP incumbents or prod them to not seek reelection in 2018, as Sen. Bob Corker (R-Tenn.) announced on Tuesday.

Seven Senate Republicans are expected to run in next year’s midterm elections: Wicker, Jeff Flake (Ariz.), Dean Heller (Nev.), Ted Cruz (Tex.), Deb Fischer (Neb.), Orrin G. Hatch (Utah) and John Barrasso (Wyo.).

Wicker, Heller and Flake, in particular, are seen as vulnerable to the coming war because of their ties to McConnell — Wicker is on his leadership team — or because they have clashed with Trump (Heller, Flake).

The early pitch from the challengers overlaps in part with the outcry of previous election cycles, but it is far more about wresting power away from traditional Republicans than Democrats.

“The Republican Congress has replaced President Obama as the boogeyman,” Steven Law, president of the McConnell-allied Senate Leadership Fund super PAC, wrote in a memo about the Alabama contest.

Businessman Danny Tarkanian, who is running against Heller and has met with Bannon, said: “The longtime politicians in the Republican Party haven’t done anything since they took over and everything is stalled. So while President Trump has tapped into the anger, McConnell hasn’t — at all.”

In Tennessee, Corker’s departure has prompted Republican leaders to find a candidate who in a contested primary race could win over both the Breitbart bloc and the party’s major supporters in the business community. They have focused on encouraging Rep. Marsha Blackburn (R-Tenn.) — an upbeat regular at conservative conferences for years — to jump in. Blackburn has said she will make a decision on the race in the coming days.

The lasting national power of Moore’s victory remains a flash point within the political ranks of the Republican Party. Republican incumbents are optimistic that the successful passage of tax cuts in the coming months will reduce the exasperation voters now feel over the failure to repeal and replace Obamacare — and say organizing successful campaigns is not easy.

“I don’t buy that the Bannon people are going to be able to get lots of Senate campaigns up and running in time,” said Ed Brookover, a former Trump campaign adviser. “It’s pretty late already in the cycle, and the fields are closer to being set than some of these potential candidates want you to believe.”

In contrast to past anti-establishment efforts in the Republican Party, going back to Barry Goldwater’s 1964 presidential bid and, more recently, the tea party movement, this crusade is not an ideological project motivated by a desire for smaller government — it’s about destroying the party’s political class in Washington, even if it jeopardizes the GOP’s congressional majorities.

The hawkish stances on foreign policy and federal spending and moral values that have defined the Republican Party since Ronald Reagan’s presidency have been shoved to the background, replaced by a blazing strain of nationalism that is driven by anti-trade and anti-immigration views — views that were heralded by Trump in 2016 but that agitators fret have been ignored in Congress.

Patrick H. Caddell, a veteran pollster who has worked with Bannon, said the “Republican electorate is in revolt.”

“The Republican Party is very close to coming apart,” Caddell said. “The voters feel economic deprivation, and their children don’t have the same opportunities. They’re becoming more anti-trade than most union Democrats, in some respects, because of anger with the global economy.”

Bannon met this week with former Colorado congressman Tom Tancredo to urge him to consider running for governor — another sign of how prominent critics of illegal immigration, like Tancredo, may return to the fore of the GOP scene.

Trump’s fingerprints are all over the ruckus — and he has volleyed complaints at Republicans who have criticized him, most notably Flake, who wrote a book about his displeasure with the GOP’s Trumpian turn. Trump has lashed back and praised Flake’s primary rival, state Sen. Kelli Ward.

But Trump is not the movement’s standard-bearer, and his positions guide the candidates and groups only to a point, as Strange’s defeat attests. More important to them is the president’s anti-establishment style — the aura of authenticity along with his aggressive take on illegal immigration. His supporters and populist leaders celebrate that approach as a model of defiance.

“I love the Trump agenda,” said persistent Nevada candidate Sharron Angle, who won a Senate GOP primary in 2010 amid the tea party’s rise and plans to run for Congress next year. But Angle said Trump’s seeming lack of concern for federal deficits has vexed her: “Sometimes, I can’t figure out the president. And I don’t think I am alone in that.”

Added consultant Tom Ingram, a Corker adviser: “Trump’s an aberration, a sign of what’s happening out there more than anything. He’s not really Republican, and he’s not really tea party. He’s just Trump.”

Democrats see an opening to possibly pick up seats if the chaos builds, even in Alabama. Moore, who has made controversial statements on race and sexuality, is facing off against former U.S. attorney Doug Jones, who will soon be joined on the trail by former vice president Joe Biden.

A Decision Desk HQ poll released Friday showed Jones only a few points behind Moore among likely voters — Moore 50.2 percent, Jones 44.5 percent.

McConnell’s former chief of staff Josh Holmes tweeted about the poll: “In a surprise to nobody, looks like the Bannon crowd created a new problem” for Trump and the GOP.

The Democratic Senatorial Campaign Committee issued a statement declaring that the result in Alabama had poured “gasoline over already raging primaries” and “throws into question how Republicans can confront the insurgent candidates who now feel even more emboldened to run. Reminder: Republicans now own Roy Moore and the uncomfortable questions he’ll provoke in races across the country.”

On the House side, there is also fear of GOP retirements, should challengers and the Bannon-Mercer partnership gain steam. But allies are waiting to see if the threats from those antagonists actually materialize.

“We’ll see if people are going to put up candidates for House races when the deadlines come up in Illinois and Texas,” said Scott W. Reed, senior strategist for the U.S. Chamber of Commerce, which opposed Moore.

“Are they going to primary House Republicans? You can huff and puff all you want, but until you file, it’s not a real race.”

Michael Scherer and Matea Gold contributed to this report.