Trump's immense GOP clout on the line in contentious Republican primary in crucial Senate battleground

Voters head to the polls Tuesday in Ohio, where a closely watched and increasingly contentious Republican Senate primary has become a high-profile test of former President Trump's immense grip over the GOP.

The winner of the primary will face off in November's general election against one of the most vulnerable Senate Democrats in a race that may determine whether Republicans win back the chamber's majority.

"If you want somebody who's going to be more liberal than Mitt Romney in the United States Senate, then vote for Matt Dolan," businessman Bernie Moreno argued at a rally in this suburban Cleveland city on the eve of the primary.

Moreno, who is the Trump-endorsed candidate in the race, compared Dolan – his main rival for the GOP nomination – to Romney, the establishment Republican senator from Utah who is reviled by Trump and the MAGA movement.