Updated May 5, 2026 at 7:07 PM CDT
This story will be updated.
Two very different decisions Republicans made about gerrymandering will be on display in Tuesday's primary contests in Indiana and Ohio.
After an effort to redraw maps in Indiana failed last year, President Trump and his political operation now seek to oust incumbent Republican state senators who helped defeat the plan.
In Ohio, new maps were required by law since multiple previous versions were struck down by the courts or passed without bipartisan support since 2021. The current map has minor changes to the state's existing boundaries — and not all of them in favor of Republicans.
These primaries come the week after a U.S. Supreme Court decision that weakened Section 2 of the Voting Rights Act and could pave the way for Republican-led states to eliminate majority-minority districts in the South as part of a larger redistricting arms race that has upended politics for 2026 and beyond.
At the same time, Trump's unpopular second-term agenda and record-low approval ratings have led to competitive races this fall for governor and U.S. Senate in Ohio, with Democrats seeing a potential path to regain control of that chamber running through the state.
Here are four things to watch in Tuesday's contest.
Trump's retribution and the Indiana state Senate
In roughly a decade of Trump offering his "complete and total endorsement" to Republicans, he rarely endorses against sitting incumbents.
But in Indiana, his political operation is targeting seven state senators who opposed the push to redraw House maps to add more Republican seats. Already one of those incumbents is out, according to a race call by the Associated Press, as Blake Fiechter won over state Sen. Travis Holdman.
Last week, NPR's Tamara Keith went canvassing with two others, including state Sen. Spencer Deery, who said the effort by the White House to play in legislative races like this runs counter to the conservative principle of state's rights.
"What is being set up here is the potential model for any party to raise ridiculous amounts of money in D.C. and then to use that to try to control the states," said Deery. "That undermines the Constitution without a law. It undermines the 10th Amendment and the ability of states to make their own decisions."
On the other hand, Trump allies said the primary challenge was about sending a message.
"This was a top political priority of President Trump's and [he] was very clear about that," said Marty Obst, a longtime Republican political consultant in Indiana, who led the redistricting push. "And the bottom line is there's consequences and accountability to those actions."
Two House incumbents in Indiana face notable primary challengers
Almost all congressional incumbents win reelection if they choose to run, and very few ever face notable or well-funded primary challengers.
This year, Indiana Republican Rep. Jim Baird and Democratic Rep. André Carson are two exceptions.
Baird is 80 years old and hasn't raised as much money as most other incumbents ($283,000 as of April 15), but has Trump's endorsement. His main challenger is state Rep. Craig Haggard, who reported raising $173,000 in the same period and touts the backing of state Attorney General Todd Rokita and more than 100 local elected officials.
Federal Election Commission data also shows the conservative Homeland PAC reported spending $200,000 in a digital ad blitz against Baird over his support for a bipartisan immigration bill called the DIGNIDAD Act. (A day later, the pro-crypto super PAC Defend American Jobs reported a half-million dollar media buy in support of Baird.)
Carson, the state's longest-serving House incumbent, has been in the seat since 2009. One of two Democrats, he faces a number of challengers at a time when some within the Democratic Party say it's time for new leadership.
Vulnerable House Democrats in Ohio will learn their opponents
Ohio's current House delegation has 10 Republicans and five Democrats. In a midterm environment that favors Democrats, that number could stay the same, even after new lines were drawn.
As Jo Ingles with the Statehouse News Bureau reported last year, the current map "would tilt districts currently represented by Democrats in Cincinnati and Toledo further right and Akron further left." That makes the path to reelection more difficult for Reps. Greg Landsman and Marcy Kaptur, but relieves some pressure on Rep. Emilia Sykes.
The top pickup opportunity for Republicans is against Kaptur, who has been in the House since 1983, the longest-serving woman in congressional history. Kaptur won by just over half a percent in 2024 under the previous district boundaries that would have voted for Trump by nearly 11%.
There's a crowded field seeking to challenge her, including former state Rep. Derek Merrin, Kaptur's 2024 opponent; state Rep. Josh Williams; former Immigration and Customs Enforcement Deputy Director Madison Sheahan; Air Force veteran Alea Nadeem; and Anthony Campbell, a healthcare data science executive.
Landsman's challengers include Trump-backed former CIA officer Eric Conroy and conservative activist Holly Adams, while none of the members of the Republican field to face Sykes has raised more than $100,000.
Will Democratic enthusiasm continue until November?
A year and a half ago, Republicans gained a trifecta in Washington. In nearly every election since then, voters have continued to swing wildly toward Democratic candidates.
For 2026, that has looked like a surge in turnout for Democratic primaries in blue states like Illinois to more conservative Mississippi and everywhere in between. In Ohio, Democrats are hoping to ride the enthusiasm among their voters and the typical midterm dynamic that favors the party out of power to flip several key races.
According to early voting data from the Ohio Secretary of State's Office, more people have voted using Democratic primary ballots than Republican ahead of Election Day, by a roughly 11% margin.
In the governor's race, former state health director Amy Acton is running unopposed in the gubernatorial primary and wealthy biotech entrepreneur and onetime presidential hopeful Vivek Ramaswamy won the Republican primary according to a race call by the Associated Press.
While the Senate race is expected to be an expensive, competitive contest in November, the primary is not. Incumbent Republican Sen. Jon Husted is unopposed, while former Democratic Sen. Sherrod Brown has one opponent who has raised little money.
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