Who will win Ohio's pivotal Senate race? Donald Trump tests the power of his endorsement.

WASHINGTON – Former President Donald Trump puts his endorsement record back on the line Tuesday in an Ohio U.S. Senate race with national implications.

Trump's candidate, businessman Bernie Moreno, is in a tight primary battle with two other Republicans, Ohio State Sen. Matt Dolan and Ohio Secretary of State Frank LaRose.

The vast majority of Trump's endorsees have won races in ruby-red areas, but he has a more mixed record in competitive states. In 2022, several of the high-profile candidates endorsed by Trump lost general elections in states like Pennsylvania, Georgia, and Arizona, their contests possibly costing the GOP a majority in the U.S. Senate.

“You gotta win, Bernie," Trump told his candidate during a Saturday rally at the Dayton airport. "Don’t leave me alone. Don’t leave me alone, Bernie."

Dolan's rise tests Trump

Dolan, a more traditional Republican, is testing the strength of a Trump endorsement with a late rise in the polls. The state legislator also enjoys endorsements from prominent Ohio Republicans, including Gov. Mike DeWine.

The winner of the Republican primary takes on incumbent Sen. Sherrod Brown, a popular Democrat who is seeking his fourth term in the U.S. Senate.

The Moreno-Dolan showdown reflects long-term, Trump-era divisions within the Republican Party, which remains torn between traditionalists and Trump's Make America Great Again movement, which is generally more conservative.

In his speech at the Dayton airport, Trump cast Moreno as the MAGA candidate while claiming Dolan is a so-called RINO, a "Republican In Name Only."

Trump compared Dolan to Sen. Mitt Romney, R-Utah, the 2012 Republican presidential nominee who has become one of Trump's most outspoken critics.

On Tuesday, Ohio's GOP voters have a chance to reflect whether they're siding with Trump's hand-picked candidate, or a more established Republican figure in the Buckeye State.

Some Trump candidates underperformed in 2022

Some Ohio Republicans have questioned whether a Trump-aligned candidate like Moreno can win a general election, saying his overt regard for the ex-president might turn off moderate and independent voters.

That issue stalked some Republican candidates during congressional races in 2022. Trump often brags about his endorsements, but he also has a history of backing overwhelming frontrunners. His track record is more mixed in competitive states.

In 2022, Trump's support boosted the Senate candidacies of Dr. Mehmet Oz in Pennsylvania, Herschel Walker in Georgia, and Blake Masters in Arizona. All three lost winnable races that fall, preventing Republicans from taking control of the Senate.

On the other hand, a 2022 Trump endorsement in Ohio lifted J.D. Vance to a Senate nomination. Vance won the general election and is now considered a vice presidential contender.

Robert Alexander, director of the Institute for Civic and Public Policy at Ohio Northern University, said a Moreno loss would be seen as a bit of a repudiation of Trump in a key state.

"Are we fully MAGA, or is there still a sense of the traditional Republican establishment in (Ohio)?" Alexander said.

Did Trump change Ohio's GOP primary?

Many Democrats hope Moreno wins the Republican nomination on Tuesday, believing the Trump-backed candidate would be the easiest opponent for Brown to beat. While Trump picked up Ohio in the 2016 and 2020 presidential elections, Brown is still a major figure in the diverse upper Midwest state.

In another sense, Trump's endorsement of Moreno already shows the former president's continuing strength among the Republican base. Moreno in recent polls has been neck-and-neck, and even leading, Dolan and LaRose.

Without the endorsement, Moreno would not be considered a contender in the Republican primary, said David Cohen, director of the Applied Politics Program at the University of Akron.

"The endorsement completely changed the complexion of the race," Cohen said.

But one question remains for voters in the crucial swing state: Will that influence translate to a victory on Tuesday?

This article originally appeared on USA TODAY: Donald Trump tests endorsement powers in key 2024 Ohio Senate race