America’s midterm election season kicks off in earnest this upcoming week with primary elections in Indiana and Ohio that promise to be the most consequential votes in recent memory — at least for Republicans.

The election in Indiana is something of a snoozer, but the vote in Ohio will be the first of several to test whether voters’ infatuation with President Trump is a figment of the Washington chattering class’s imagination or something the party will have to contend with come November. 

On the second Tuesday of the month, May 10, voters in Nebraska will decide who will face off in November in a race to succeed the Republican governor, Pete Ricketts, who has reached his term limit, and Republicans in West Virginia will vie for two congressional slots on the November ballot.   

Polls will be open in Kentucky, Pennsylvania, North Carolina, Oregon, and Idaho on May 17, and May 24 will see primary elections in Alabama, Arkansas, and Georgia, as well as run-offs in Texas, which held its first-round primary on March 1.

Pollster Kai Chen Yeo, who has been conducting focus groups around the country this spring for Echelon Insights, says one issue dominated those discussions — the economy.

“The cost of a burger, cheese, or milk at the store is creating a rare bipartisan agreement that the country is not headed in the right direction,” Ms. Yeo said.

Mr. Trump, she said, remains on the minds of Republican voters, but fewer of them are clamoring for his return to the national stage in 2024 than there were when President Biden was inaugurated in early 2021.

“Trump’s level of influence over Republicans’ mental real estate is not as high as Democrats tend to think it is,” Ms. Yeo said. 

Two of the races testing that thesis are in Georgia later this month, and both are personal for the former president. Mr. Trump narrowly lost the state in 2020 and continues to blame that loss on state officials who refused his demands that they change the results in his favor after Election Day.

Georgia’s incumbent governor, Brian Kemp, is running for re-election and enjoys a double-digit lead over his Trump-anointed challenger, David Perdue, who lost his seat in the United States Senate in 2020. Whoever wins will, in all likelihood, face in November a progressive celebutante, Stacey Abrams.

The incumbent secretary of state in Georgia, Brad Raffensperger, who oversees elections in the state, is also being challenged from the right by Congressman Jody Hice. The latest polls put that race much closer.

One Georgia race that isn’t close is that for the GOP’s U.S. Senate candidate. A former football star and Olympic bobsledder, Herschel Walker, is Mr. Trump’s choice to face off against Senator Warnock, a first-term Democrat, in November. Mr. Walker is polling in the mid-60s, a lead a prominent Republican pollster, Frank Lunz, called “insurmountable” for his four competitors.    

All the Georgia candidates will need to get more than 50 percent of the vote to avoid runoffs on June 21.

Four other Senate primaries are being called bellwethers for the Trump faction of the GOP — Alabama, Ohio, North Carolina, and Pennsylvania. 

The Alabama race is the least pivotal of the lot because Mr. Trump withdrew his support for Congressman Mo Brooks in April when it became clear that Mr. Brooks was foundering. He is polling third in the race, behind front-runner Mike Durant, a former Army helicopter pilot who was shot down and taken hostage in Somalia in 1993, and Katie Britt, a 40-year-old lawyer and former chief of staff to the man whose seat will be filled in November, Senator Shelby.

In the North Carolina Senate primary, the Trump favorite is Congressman Ted Budd, who is up against Pat McCrory, the former governor most famous nationally for signing a bill regulating which public restrooms transgender residents are required to use. Recent polls have put Mr. Budd roughly 10 points ahead of his opponent.

If MAGA world’s candidate in Ohio, J.D. Vance, wins the primary, Mr. Trump will almost certainly take credit, and rightly so. The endorsement of Mr. Vance over his six Trump-friendly rivals in the final days of the campaign immediately pushed him to the top of the polls in the race to succeed Senator Portman, who is retiring this year.

The wild card in the Ohio race is Matt Dolan, a conservative who has urged Mr. Trump to stop what Mr. Dolan says is lying about the outcome of the 2020 election. Mr. Dolan has seen a late surge in his polling, enough so that Mr. Trump felt the need to issue a statement this week saying the Ohio state senator is “not fit” to serve in the U.S. Senate.

A win by Mr. Vance in Ohio is widely expected to set him up for a win in November. In Pennsylvania, however, not so much. Mr. Trump has endorsed television doctor Mehmet Oz over six others vying for the GOP nomination — hedge fund CEO Dave McCormick and former television commentator Kathy Barnette among them — but with the race to succeed retiring Senator Toomey being described as one of the few genuine toss-ups of 2022, the GOP winner is by no means a shoe-in.

On the Democratic side in Pennsylvania, the party’s progressive wing enjoys an edge with its chosen candidate, Lieutenant Governor John Fetterman, ahead in a four-way race for the nomination. Mr. Fetterman, who stands 6’8” tall and looks more like a blue-collar ironworker than a progressive firebrand, has made a name for himself railing against deindustrialization of the heartland by fat-cat capitalists and for a $15 minimum wage and Medicare for all.  

“The open Pennsylvania Senate seat is Democrats’ best offensive opportunity on the midterm map,” a Cook Political Report analyst, Jessica Taylor, wrote in mid-April. It is also “the rare contest this cycle where both parties’ primaries on May 17 are competitive and will tell us a lot about the direction of each.”