Senate Republicans started the cycle with a good electoral map that gave them some hope that they could gain seats, even in a mid-term election when history strongly suggests that they should lose them. But, a growing schism in the Republican Party is threatening to erode many of the advantages Senate Republicans have, and is beginning to jeopardize their ability to gain seats as they are forced to fight multiple primaries that have the potential to provide Democrats with opportunities that didn’t exist just a month ago.

President Trump gets most of the credit for the growing schism in the party as his constant criticism of the GOP congressional leadership, particularly Senate Majority Leader Mitch McConnell, has succeeded in driving a wedge between congressional Republicans (read: the establishment) and Trump Republicans. The realities of getting any major legislation through a narrowly divided Senate notwithstanding, Trump has successfully sold the message to his base that the GOP-controlled Senate is responsible for the failure of his legislative agenda. The result is that Trump voters are angrier now than they were when they voted for Trump almost a year ago, but instead of being angry at Hillary Clinton or Democrats, they are now turning their rage on the establishment, and anyone who can be associated with it.

If Trump has widened the schism, then former aide Steve Bannon has poured gasoline in it and struck a match. Using Roy Moore’s victory over appointed U.S. Sen. Luther Strange in the GOP run-off in the special election in Alabama as a springboard, Bannon has declared war on every Republican Senate incumbent up in 2018, promising to recruit primary challenges against them (except Ted Cruz). According to those familiar with Bannon’s thinking, he believes that the pursuit of a nationalistic policy agenda can succeed and grow the party, but achieving that requires “suffocating” the GOP establishment. And, he appears not to consider – or not care – about the consequences, not the least of which is actually winning general elections and maintaining, if not growing, the GOP majority.

Whether Bannon’s assumption is correct is up for debate. Successfully suffocating the establishment may well create the “new” Republican Party he envisions. It is equally possible that the party that once aspired to be an inclusive “big tent” could become a small yurt.

At the moment, Bannon’s war on Senate incumbents is beginning to look a lot like the Tea Party’s 2010-2012 war on the establishment. The Tea Party won some battles in that war, and their advocates would even say that they were largely successful in moving the party to the right and perhaps even setting the table for Trump’s rise. But, the Tea Party lost more than it won in the 2010 and 2012 cycles as it got behind candidates who couldn’t win general elections either because they were too conservative to win statewide or were utter train wrecks as candidates, and sometimes both.

Bannon’s war – at least for the time being – appears less ideological than the Tea Party’s battle. Whereas Tea Party candidates talked about smaller government, reduced spending and eliminating deficits, Bannon-backed candidates simply talk of backing Trump’s agenda, which is a moving target, and upending the establishment. But, like the Tea Party circa 2010, Bannon and his campaign against the establishment has become the bright shiny object that many GOP Senate candidates are chasing in the hope of securing Bannon’s endorsement. It seems that one requirement for the endorsement is a promise not to support McConnell as party leader.

The reality is, though, that Bannon’s campaign may well backfire by creating opportunities for Democrats that wouldn’t exist absent his efforts. And, although some of the states being targeted are solidly Republican, the time, money and resources that will go into the promised primaries will hurt the party’s efforts to pick up Democratic-held seats both by robbing those races of resources and by providing Democrats fodder to tag GOP nominees as too extreme. In 2012, when Todd Akin, the Tea Party-backed nominee in Missouri, uttered his claims about “legitimate rape,” he become the political equivalent of a virus that quickly spread among Senate candidates who were constantly questioned about their views on Akin and his beliefs. Among the candidates that Bannon is recruiting, there is a good chance that another Todd Akin (or Christine O’Donnell or Richard Mourdock or Sharon Angle) emerges.

Among the eight GOP seats on the ballot next year, two incumbents – U.S. Sens. Jeff Flake in Arizona and Dean Heller in Nevada – are guaranteed to face competitive general elections in which both are even money bets against the presumptive Democratic nominees. Both now face Bannon-backed primary opponents. The Republican primary electorate in both states is very conservative, putting Flake and Heller in jeopardy. If one or both of these incumbents lose the nomination, these seats become much more difficult for Republicans in the general election.

Taking Cruz out of the mix, the remaining four incumbents – U.S. Sens. Roger Wicker (MS), Deb Fischer (NE), Orrin Hatch (UT) and John Barrasso (WY) – and the open seat in Tennessee where U.S. Sen. Bob Corker is retiring, all represent very Republican states. Hatch, if he runs, and Wicker may be vulnerable to the right primary challenge. The threat to find primary opponents against Fischer and Barrasso is especially curious since they are solid conservatives. It seems that their only offense is their support for McConnell.

Bannon started rolling out endorsements this week in many of the top Senate races. He also went to Arizona to appear at a rally with Kelli Ward, who is running against Flake in Arizona. This weekend, he will be in at the California Republican Party’s semi-annual meeting in Anaheim, although Republicans won’t be competitive in the Senate race there.

Bannon Endorsed Senate Candidates

State Incumbent Bannon Candidate Arizona Sen. Jeff Flake (R) Kelli Ward Nevada Sen. Dean Heller (R) Danny Tarkanian Tennessee OPEN – Corker (R) Marsha Blackburn Montana Sen. Jon Tester (D) Matt Rosendale West Virginia Sen. Joe Manchin (D) Patrick Morrisey Wisconsin Sen. Tammy Baldwin (D) Kevin Nicholson

Despite the GOP nature of the states in which Bannon is targeting Republican incumbents, Democrats are working to recruit credible candidates in the event lightning strikes and Republicans end up with an unelectable nominee. If Democrats need to gain three seats to win the majority, they have to put a third GOP-held seats in play, giving them another reason to make sure they have candidates in place even in races that look impossible today. The open seat in Tennessee is a good example. It is a solidly red state that Trump carried by 26 points. Bannon has endorsed U.S. Rep. Marsha Blackburn, a candidate that the establishment can support, but she isn’t the only candidate seeking the nomination. Democrats are recruiting former two-term Gov. Phil Bredesen, who served from 2003 – 2011 and who is giving the race serious consideration. If Bredesen runs then this seat becomes a toss up. Bredesen wouldn’t have given the contest a passing glance if GOP U.S. Sen. Bob Corker had run for re-election and Bannon had not inserted himself into the race.

There are also establishment-versus-Bannon primaries taking place in states where the GOP is targeting Democratic incumbents. In both Indiana and West Virginia, Republicans are hosting primaries that will become referenda on the establishment. In Indiana, U.S. Rep. Todd Rokita is chasing Bannon’s endorsement, while U.S. Rep. Luke Messer is considered a more mainstream Republican. It is worth remembering that Democratic U.S. Sen. Joe Donnelly won this seat in 2012 in part because Republicans nominated Richard Mourdock, a Tea Party candidate, who proved to be out of step with general election voters. In West Virginia, Bannon has endorsed Attorney General Patrick Morrisey against U.S. Rep. Evan Jenkins. Despite giving Trump a 42-point victory, voters here tend to opt for more mainstream candidates for statewide office, including Democratic incumbent Joe Manchin.

It is increasingly likely that GOP primaries in Montana and Wisconsin will host the kind of primary that will distract from the party’s ability to make the general elections against U.S. Sens. Jon Tester and Tammy Baldwin toss up races. At this point, it appears that Republicans will have nominees ready to challenge the establishment in Ohio against U.S. Sen. Sherrod Brown, in Pennsylvania against U.S. Sen. Bob Casey, and in Virginia against U.S. Sen. Tim Kaine who could make it harder for Republicans to make these races competitive.

Republican strategists are holding out hope that, like many Tea Party candidates in 2010 and 2012, Bannon won’t have the resources to support his candidates. There were some Tea Party candidates who were successful fundraisers; Sharron Angle in Nevada comes to mind. But, since the Tea Party didn’t really have a formal structure or the infrastructure in place to support candidates, these candidates were largely on their own.

Bannon seems acutely aware of this and has been traveling the country to meet with GOP mega donors who could help fund his effort. He has even gone as far as seeking out at least one donor who has supported McConnell in the past. In addition, it appears that the Mercer family, who gave millions to help elect Trump, will provide some of the funding. They have already given $300,000 to a super PAC supporting Kelli Ward, who is running against Flake in Arizona. The Great America PAC, a super PAC started last cycle to support Trump, appears to be the vehicle that will support Bannon’s efforts. The group ran television ads against Luther Strange in the Alabama Senate run-off, and just started running ads against Democrat Doug Jones in the general election.

There are lots of questions that need to be answered between now and next fall that range from the results of these GOP primaries to the overall political landscape. Perhaps the biggest unknown is voter turnout. Will the Democratic base be as motivated as they are now? Will Trump voters turn out at the same level they did in 2016, or will they be more like Obama voters, who went to the polls only when he was on the ballot despite the party’s effort to motivate them?

The one thing that is clear is that Bannon’s war on Senate Republicans is eroding the party’s ability to make gains in 2018. It is too soon to say that the majority is in play; at this point that would require Democrats to hold all of their seats and pick up three Republican-held seats. However, it is fair to say that scenario is not the unthinkable proposition it was a month ago. If the national political environment further deteriorates for Republicans to the point that a wave along the lines of 2014 begins to develop, or they nominate a train wreck or two, Democrats could have a shot at winning the narrowest of majorities.

The great irony of Bannon’s efforts is that he is unlikely to achieve his objective of passing a nationalistic legislative agenda. If he is successful, the Senate Republican conference would certainly move further to the right, and its leadership may change, but it won’t be any easier to pass legislation. In fact, it is likely to get a lot harder, but that’s a subject for another column.