Donald Trump casts himself as deciding factor in GOP election wins

President Trump said he’s the magic touch for struggling Republican candidates after his picks won a series of victories Tuesday.

Trump-backed candidates claimed victory in a high-stakes special congressional election in Ohio and in a trio of other primaries. Kris Kobach, a controversial Trump ally in Kansas, leads by a thin margin in his quest to oust the sitting governor in a Republican primary.

“5 for 5!” Mr. Trump said on Twitter Wednesday, which marked 90 days until the midterm elections when control of the House and the Senate will be on the line.

Liberal forces also claimed momentum after they turned back an effort to make Missouri a right-to-work state and their picks won House primaries in Kansas and Michigan.

Rashida Tlaib is on the verge of becoming the first Muslim woman in Congress after winning the Democratic Party’s nomination in Michigan’s 13th Congressional District.

They also saw a major advance in the St. Louis County prosecutor’s race, which had become a major showdown between Democrats’ old guard and the gate-crashing liberals in Missouri.

Wesley Bell defeated incumbent prosecutor Bob McCulloch, who was targeted by grassroots activists over the way he handled the police shooting of a black man, Michael Brown, in Ferguson in 2014.

“Wesley Bell’s success shows us that voters are hungry for prosecutors who understand the structural racism that undergirds our criminal justice system and are committed to delivering on reforms that can fundamentally alter it, like ending cash bail and the independent review of police misconduct,” said Jim Dean, chairman of Democracy for America.

The left wing of the Democratic Party — including its newest star, Alexandria Ocasio-Cortez, who knocked off Rep. Joseph Crowley in New York’s June primary — saw its favored candidates fall in primary races in Missouri, Michigan and Kansas.

Still, the success for Mr. Trump and the liberals signaled growing pressure within both parties away from the political center. Analysts say the trend could pose problems for both parties in the general election.

Nowhere was that clearer for Republicans than in Kansas, where Mr. Kobach, an architect of the president’s immigration agenda, held a 191-vote lead over Gov. Jeff Colyer after more than 311,000 ballots had been cast, opening up the possibility of a recount. The race was not called because provisional and mail-in ballots had yet to be tallied.

The outcome of the race in Ohio’s 12th Congressional District also remained up in the air, though Mr. Trump claimed victory, saying he helped power Troy Balderson to a win over Democrat Danny O’Connor.

The president made a last-minute stop in the state over the weekend and said he helped turn the tide.

“The Republicans have now won 8 out of 9 House seats, yet if you listen to the Fake News Media you would think we are being clobbered,” he said in another tweet. “Why can’t they play it straight, so unfair to the Republican Party and in particular, your favorite President!”

An automatic recount could be triggered in Ohio if the final tally shows the candidates separated by less than half a percentage point.

The outcomes were less suspenseful in Michigan.

Mr. Trump’s preferred candidates in the Senate and gubernatorial primaries — John James, an Iraq War veteran, and Bill Shuette — won.

Mr. Trump also declared victory in Missouri after Josh Hawley, the state’s attorney general, won the party’s nomination for the Senate, putting him on a collision course with Democratic Sen. Claire McCaskill in November.

“As long as I campaign and/or support Senate and House candidates (within reason), they will win!” Mr. Trump said on Twitter. “I LOVE the people, & they certainly seem to like the job I’m doing. If I find the time, in between China, Iran, the Economy and much more, which I must, we will have a giant Red Wave!”

Democrats said talk of a red wave rings hollow given that Mr. Trump won the Ohio district by more than 10 points in 2016, yet Mr. O’Connor was nearly tied with Mr. Balderson.

Tom Perez, chairman of the Democratic National Committee, said the Ohio race “wasn’t supposed to be competitive.”

“But last night proved Democrats can close the gap anywhere, even in the reddest districts,” Mr. Perez said. “If we’re keeping it this close in this district now, it’s a good sign for our chances across the country this November.

“There are dozens of seats on the line in November that are major red-to-blue opportunities — and more than 60 Republican-held congressional districts currently rate more competitive for Democrats than OH-12,” he said in a fundraising pitch.

Democrats need to flip 23 seats to win the House.

Political analysts agreed with Democrats’ assessment.

“If anything, tonight’s #OH12 result reinforces our view that Dems are substantial favorites to retake the House in November,” said David Wasserman, of the Cook Political Report, a nonpartisan election tracker.

Republican-aligned groups warned that their party’s candidates need to get their act together if they hope to retain control of the House.

“While we won tonight, this remains a very tough political environment, and moving forward, we cannot expect to win tough races when our candidate is being outraised,” said Corry Bliss, executive director of the Congressional Leadership Fund, which spent millions of dollars on behalf of Mr. Balderson. “Any Republican running for Congress getting vastly outraised by an opponent needs to start raising more money.”