The super PAC set up by allies of Sen. Mitch McConnell to keep Republicans in power has spent almost $5 million in this election cycle. Under normal circumstances, that would be good news for the party, an indication of its financial strength and tactical savvy. Today it’s bad news, because over 80 percent of the money has gone to attacking Republican rebels who are challenging party incumbents.


Much of the cash has been pouring in to a special Senate contest in Alabama, where a far-right challenger to McConnell’s favored candidate is leading in a race to replace Attorney General Jeff Sessions. There’s a similar dynamic at play in Arizona, where a McConnell-friendly Republican is facing a formidable insurgent in 2018. Other tests are ahead.


At the White House, President Donald Trump does more to provoke party combat than to make peace; he has no allegiance to Republicans. Steve Bannon, his venomous alt-right political guru, told Charlie Rose last week on “60 Minutes” that he’s eager to take out Republicans he considers too moderate or insufficiently supportive of Trump.


The consequences for next year’s elections are to imperil Republican control of the House and put Senate leaders on the defensive. Instead of focusing on four races where they thought they could add to their two-seat majority, they have to guard against losing a couple.


A prime indicator of this bitter divide is the way the McConnell-controlled political action committee spends its money. At this stage two years ago, the Senate Leadership Fund hadn’t spent a penny on election contests, and for the entire 2016 cycle it doled out just $482,000 against Republican challengers. It’s already spent eight times that much this year against Republicans.


The Alabama primary is where McConnell is trying to protect Sen. Luther Strange, appointed after Sessions went to the Justice Department. But Strange is trailing the right-wing former chief justice of the Alabama Supreme Court, Roy Moore. Moore was removed twice from his judicial post, once for defying a federal judge’s order to move a Ten Commandments monument from his courtroom and then for ordering state judges to withhold marriage licenses from gay and lesbian couples despite a U.S. Supreme Court decision legalizing same-sex unions.


The two Senate Republican incumbents most vulnerable to Democrats in 2018, Jeff Flake of Arizona and Dean Heller of Nevada, also face primary challenges from Trumpist candidates. Flake’s outspoken criticism has earned him special enmity from the White House, and McConnell’s PAC is attacking his main primary challenger, Kelli Ward.


Bannon met last week with Danny Tarkanian, the Nevada Republican whom he’s supporting in a primary challenge against Heller. The Trump confidant, who left the White House last month but remains close to the president, said in the “60 Minutes” interview that he considered McConnell and House Speaker Paul Ryan to be political enemies, accused the Roman Catholic church of pandering to “illegal aliens” and charged that three foreign-policy advisers to Republican presidents, Colin Powell, Condoleezza Rice and Brent Scowcroft, are “idiots.”


Initially, Republicans thought they’d be able to focus their energy on adding to their Senate majority by going after Democratic incumbents in states that went overwhelmingly for Trump, like West Virginia, Indiana, Missouri and North Dakota. Bitter Republican primaries could jeopardize these prospects.


The civil war also is threatening the party in House elections. Some House moderates, like Pennsylvania’s Charlie Dent, are retiring, sick of fighting the Trump element. Look for more Republican retirements in the weeks ahead.


Here’s another indicator: In 2015, House Republicans turned to Ryan to unify the party after pushing out Speaker John Boehner. Trump, however, has not hidden his disdain for Ryan. That’s had an effect. At a candidate forum at the Minnesota State Fair in August, four Republican candidates in swing districts refused to commit themselves to supporting Ryan’s re-election as speaker.


Albert Hunt is a Bloomberg View columnist. Readers may email him at ahunt1@bloomberg.net.