In Indiana Primary Elections, Most Trump-Backed Challengers Beat Incumbents

President Trump promised political payback last year when Indiana state senators from his own party voted down his plan to redraw the state’s congressional map to help Republicans.

On Tuesday, he got much of what he wanted, as at least five of the seven anti-redistricting Republicans facing Trump-backed challengers lost their primaries, according to The Associated Press. The results reflected Mr. Trump’s continuing sway over Republican voters and his ability to enforce political consequences for Republican officeholders who defy him.

In the other races, at least one incumbent won his primary and another race remained too close to call.

State legislative primaries are often low-drama affairs, but Mr. Trump’s involvement brought unusual levels of attention and outside spending. The president issued social media endorsements to the seven challengers and hosted some of them at the White House, while outside groups aligned with Mr. Trump poured money into the races.

As the challengers emphasized their ties to Mr. Trump, many of the incumbents focused on their own conservative credentials, as well as endorsements from groups supporting farmers, gun rights or abortion restrictions.

Rather than a contest between moderates and conservatives, the primaries became a test of how much deference Republicans owe Mr. Trump and how much control the president holds over rank-and-file voters.

“It’s not that anyone is less or more pro-life,” said Lt. Gov. Micah Beckwith, a Republican redistricting supporter who backed most of the Trump-endorsed challengers. “It’s really that, do you understand the battle we are in, and do you understand the role Indiana plays in that battle on a national stage?”

State Senator Spencer Deery, one of the anti-redistricting incumbents, described the election as a test of how much sway Washington policymakers and their allies have over state policymaking.

“What’s at stake,” he said, “is the question of whether state legislators are going to be free to listen to their constituents and to govern their state without the outside meddling of enormous financial sums of dark money.”

On Tuesday, voters had diverging views of the political landscape and of the president’s endorsement.

In Granger, Ind., along the Michigan border, Tony Xouris said redistricting was his top issue and that he turned out to vote for the Trump-backed challenger to Senator Linda Rogers, who voted against the redrawn map.

“She lost my vote,” said Mr. Xouris, a semiretired insurance agent. “She’s a RINO. She’s a bad Republican.”

But outside the polls in Schererville, Ind., near Chicago, Matt Bartz said he was voting for Senator Dan Dernulc even though Mr. Trump had endorsed a challenger.

“I’m a Trump supporter,” said Mr. Bartz, a retired steelworker. “I was under the understanding that he wanted states to regulate themselves, take care of themselves, but now he’s coming back with this revenge type of thing and I’m not happy with that.”

The races also split political leaders in Indiana, where Republicans have amassed power over the last 20 years, but where there are longstanding fissures between the party establishment and an ascendant movement that hews closely to Mr. Trump.

Gov. Mike Braun and Mr. Beckwith, along with some members of the congressional delegation, came out in support of many of the challengers.

On the other side, former Gov. Mitch Daniels, who helped usher in Indiana’s era of Republican dominance, became a leading voice against redistricting. His successor as governor, former Vice President Mike Pence, endorsed one of the incumbents seeking re-election.

The rupture began last year when Mr. Trump was pushing redistricting nationwide in a bid to gain seats in Congress in the midterm elections. Several Republican-led states quickly fell in line, and some Democratic-led ones moved to counter with their own maps. But a critical mass of Indiana lawmakers remained opposed to the plan to draw a map that would position Republicans to flip the state’s two U.S. House seats held by Democrats.

When lawmakers returned to Indianapolis in December, the Republican-led House approved a new map. But the Republican-controlled Senate said no, with a slim majority of Republicans joining Democrats to vote the bill down even as Mr. Trump threatened political consequences.

“Any Republican that votes against this important redistricting, potentially having an impact on America itself, should be PRIMARIED,” Mr. Trump wrote in a November social media post that referred to two senators as Republicans in name only.

He soon followed through on that promise, endorsing challengers to seven of the eight anti-redistricting Republicans who ran for re-election this year. Other Republicans who voted against the bill have two years remaining in their terms or did not run for re-election.

Kim Bellware, Robert Chiarito and Nick Corasaniti contributed reporting.