Establishment Republicans standing in the way of President Donald Trump’s agenda are falling like dominoes heading into the midterm elections in 2018, as Breitbart News Executive Chairman and former White House chief strategist Stephen K. Bannon ramps up his “season of war” on the political class.

The latest failed Republican to tap out is Sen. Jeff Flake of Arizona, who announced on Tuesday he will not seek re-election after originally planning to. Flake’s decision to avoid what would have been a bruising and likely unsuccessful battle to win renomination by Arizona Republican voters for the U.S. Senate seat he currently holds comes as Bannon and nationally-syndicated radio host Laura Ingraham campaigned for his primary challenger, Dr. Kelli Ward, in Arizona last week.

All three appeared in Washington, D.C., at the “Breitbart Embassy” on Capitol Hill, where they were attending a book party for Ingraham’s new book. It also comes on the heels of the pro-Trump Super PAC Great America PAC endorsing Ward for the U.S. Senate as part of a new slate of candidates to refresh the Republican Party nationally.

The crowd was packed out for @kelliwardaz tonight w/ Steve Bannon! pic.twitter.com/H2tcfmrkOI — Laura Ingraham (@IngrahamAngle) October 18, 2017

They are going to reap the whirlwind and "that whirlwind is Kelli Ward," Steve Bannon says in remarks that sound like an endorsement. #AZSEN — Dan Nowicki (@dannowicki) October 18, 2017

“Today the Trump movement collected the scalp of America’s number one Never Trumper,” Andy Surabian, a senior adviser to the Great America Alliance—a sister organization of the PAC—told Breitbart News exclusively on Tuesday afternoon. “Jeff Flake represents everything that is wrong with Mitch McConnell’s failed vision of the Republican Party. President Trump’s America First movement is on a winning streak now that Jeff Flake has been left on the ash heaps of political history alongside Luther Strange and Bob Corker. And rest assured that Mitch McConnell and the rest of his Never Trump establishment cohorts are next on our agenda.”

Arizona voters are the big winner in @JeffFlake's decision to not seek reelection. They deserve a strong, conservative in the Senate 1/2 — Dr. Kelli Ward (@kelliwardaz) October 24, 2017

Who supports @POTUS & the 'America First' agenda. Our campaign proudly offers an optimistic path forward for Arizona & America #MAGA 2/2 — Dr. Kelli Ward (@kelliwardaz) October 24, 2017

Surabian is a former White House and Trump campaign official. During his tenure in the White House, he was Bannon’s deputy. In the campaign, he ran the war room, which handled rapid response to attacks the media and Democrat Hillary Rodham Clinton were leveling against the now-president of the United States.

Ward, a former state senator who previously challenged Sen. John McCain (R-AZ) in 2016 but lost after now-President Donald Trump endorsed McCain late in his primary after Trump became the GOP nominee that year, is a doctor and strong conservative. Despite establishment GOP efforts to desperately find an alternative to Ward, she is easily the favorite now to win the nomination and face off against likely Democrat nominee Rep. Kyrsten Sinema (D-AZ) in November 2018.

SLF with some 🔥🔥🔥 towards Bannon and Kelli Ward in its statement on Flake pic.twitter.com/AdmV5pTJBn — Ben Jacobs (@Bencjacobs) October 24, 2017

Bannon on his war on the GOP establishment: "It's an open revolt, and it should be." Says revolt is going from Alabama to Arizona. #AZSEN — Dan Nowicki (@dannowicki) October 18, 2017

Flake’s fall, which is significant in and of itself, is also even more consequential because it comes after a wave of other establishment Republicans out of step with President Trump’s agenda have also disintegrated. On Sept. 26, appointed incumbent Sen. Luther Strange of Alabama lost a GOP primary runoff to conservative Judge Roy Moore after GOP establishment-connected institutions spent more than $30 million trying to prop up Strange and take down Moore. As that happened, just hours before the polls closed, Sen. Bob Corker (R-TN) announced his impending retirement.

McConnell and his allies poured millions upon millions of dollars into Alabama to prop Strange up and bash Moore, but they failed miserably as Moore beat Strange—despite Strange getting a Corker-inspired endorsement from President Trump—by nearly 10 percent. Corker announced his retirement just hours before the polls closed, and a day after Breitbart News released an investigation into Corker’s sweetheart real estate dealings in Alabama. Meanwhile, subsequent Breitbart News investigative reporting into Tennessee Gov. Bill Haslam has led to Haslam deciding against running for the U.S. Senate.

Great America PAC, which endorsed Ward and Moore and has now backed Rep. Marsha Blackburn (R-TN) for the U.S. Senate in Tennessee to replace Corker, is also leading the way in other states like West Virginia, Wisconsin, and Montana, backing anti-establishment Senate candidates in those places as well.

In West Virginia, McConnell is backing establishment Rep. Evan Jenkins (R-WV)—a former Democrat who supported Hillary Clinton for president in 2008—for U.S. Senate, while conservatives led by the Great America PAC are supporting Attorney General Patrick Morrisey. The winner will face incumbent Sen. Joe Manchin (D-WV) in November 2018.

In Wisconsin, conservatives including Great America PAC are rallying behind businessman and Marine Corps veteran Kevin Nicholson—who is publicly opposing McConnell for Majority Leader—while the establishment in the state gets behind state Sen. Leah Vukmir. Vukmir has been under fire back home for refusing to stand with the voters of her state against McConnell.

And in Montana, McConnell is desperately searching for another candidate besides anti-establishment statewide insurance auditor Matt Rosendale, despite Rosendale gaining significant traction in the state and being the clear frontrunner for the GOP nomination. The winner will face incumbent Sen. Jon Tester (D-MT) in November 2018.

Morrisey, Nicholson, and Rosendale—like Ward, Moore, and Blackburn—publicly embrace Bannon’s efforts to move the Republican Party in a new direction towards economic nationalism and success and away from the failures of globalism. That fight is embodied in battles over trade and immigration policy, perhaps no better than in the battle of 2013 over the “Gang of Eight” amnesty bill.

Met w/ Steve Bannon a few weeks ago. Thrilled to have earned his support! I’m running to fight D.C. status quo. Let’s replace Jon Tester. pic.twitter.com/ZmHru8actD — Matt Rosendale (@MattForMontana) October 18, 2017

I've had my share of run-ins w/ #fakenews and the establishment in WV. That's why I support Bannon's efforts to drain the DC swamp! #wvsen — AG Patrick Morrisey (@MorriseyWV) October 19, 2017

"The Steve Bannon primary in Wisconsin is over and Kevin Nicholson has won." Humbled by this huge endorsement. (1/2) — Kevin Nicholson (@KevinMNicholson) October 17, 2017

Flake, interestingly, was an original member of the pro-amnesty “Gang of Eight” that pushed to reward every illegal alien in America with citizenship in 2013. Flake was in that group with Sens. John McCain (R-AZ), Lindsey Graham (R-SC), Marco Rubio (R-FL), Dick Durbin (D-IL), Chuck Schumer (D-NY), Michael Bennet (D-CO), and Bob Menendez (D-NJ). Flake helped the U.S. Senate pass the amnesty bill, which eventually failed in the House of Representatives due to underwhelming support from the American people.

The Gang of Eight led in many ways to the eventual defeat of Rubio in the presidential primaries in 2016 and the political irrelevance of most of its original members. Menendez was indicted in 2015 for alleged corruption crimes he is now on trial for—and is expected to be convicted of, leading to his likely eventual expulsion from the U.S. Senate.

Bennet is rarely heard from in national political circles, and the year after the U.S. Senate passed this bill saw a multi-seat swing towards the GOP in a wave election that has left the Democrats in the U.S. Senate minority ever since—meaning Schumer and Durbin, though in leadership of their party, are essentially unable to make policy, as they have no control over their chamber while their party is in the minority.

Democrats are not expected, given the extraordinarily favorable Senate map for the GOP in 2018, to retake the Senate in the midterms, so the Gang of Eight was in many ways the downfall of most of its members. Shortly after the GOP wave in 2014 following the failed amnesty push in 2013, President Trump blew past 16 other Republican candidates in the primaries—and past Democrat Hillary Rodham Clinton in the general election—to become President of the United States while running hard against amnesty and with promises to build a wall along the U.S. border with Mexico.

In other words, Bannon–and other Trump loyalists throughout the economic nationalist grassroots movement across the country–are winning the war.

There's a war for the future of the GOP and the only person who seems to be fighting it is Steve Bannon. Its really dispiriting. — Tim Miller (@Timodc) October 24, 2017

Going to wake up one day and have Chris McDaniel, Chemtrail Kelli, Sheriff Joe, and Roy Moore as nominees & still nobody will fire a shot. — Tim Miller (@Timodc) October 24, 2017

Instead our side will pretend like our candidate is actually the Trumpiest one and then endorse the lunatic when it doesn't work. — Tim Miller (@Timodc) October 24, 2017

And, as the very heart of the establishment–former Jeb Bush spokesman and Never Trump leader Tim Miller–will admit, the establishment is losing the war badly.