Ugly GOP primary comes to an end as swing state voters set to decide who will face tough Democrat incumbent

Nevada's Sam Brown and Jeff Gunter are battling to see who will face incumbent Democrat Sen Jacky Rosen in November

RENO, Nev. – The brutal Republican primary in one major swing state is finally coming to an end as voters head to the polls Tuesday to determine which candidate will face off against what is expected to be a tough Democrat incumbent.

Former U.S. Army Capt. Sam Brown and former President Trump official Dr. Jeffrey Gunter traded blow after blow in the weeks leading up to the Nevada primary as each sought to paint themselves as the true "America First" candidate in the race. 

Both fought — publicly and privately — for former President Trump's endorsement, a battle Brown, an Afghanistan war veteran who underwent a catastrophic injury while deployed in 2008, ultimately won with a last minute weigh-in by the presumptive Republican presidential nominee on Sunday.

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Former U.S. Ambassador to Iceland Jeff Gunter, left, and former U.S. Army Capt. Sam Brown. (State Department, Sam Brown for Nevada)

Gunter, however, hopes his "MAGA" messaging since the launch of his campaign last year, as well as his service to Trump as his ambassador to Iceland, will propel him to a surprise, come-from-behind victory.

The winner will likely face the daunting task of taking on Democrat Sen. Jacky Rosen and the well-financed operation her party hopes will keep the Silver State firmly blue in a year when Republicans are expected to perform well across the country.

Polling on the race has been sparse, with both Gunter and Brown each touting their own internal polls as evidence they hold the advantage.

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Former President Trump points to the teleprompter and says it is not working, as he speaks during a campaign rally at Sunset Park in Las Vegas on June 9, 2024. (JIM WATSON/AFP via Getty Images)

Gunter has largely funded his own campaign, but Brown has had the backing of national Republicans who see him as the best chance to flip the seat. That backing appears to be what ultimately pulled Trump to his corner, making him the widely viewed favorite to win the race.

Brown also has the backing of Nevada's popular Republican Gov. Joe Lombardo, a figure who largely stays out of the spotlight and rarely weighs in such instances of increased national attention.

Gunter has picked up his own set of high profile endorsements in the race, including Reps. Matt Gaetz, R-Fla., and Paul Gosar, R-Ariz., as well as former Republican Congressman and New York gubernatorial candidate Lee Zeldin.

Sen. Jacky Rosen (D-NV) waits to speak during a groundbreaking ceremony at the Brightline West Las Vegas station on April 22, 2024 in Las Vegas. (Ethan Miller/Getty Images)

Brown and Gunter are facing a crowded primary field that includes former state Rep. Jim Marchant and veteran Air Force pilot Tony Grady. Rosen faces no serious opposition in her primary.

Democrats currently hold a slim 51-49 majority in the Senate, and the Nevada race is being viewed as a top flip opportunity for Republicans, along with races in West Virginia, Montana, Ohio, Pennsylvania, Michigan, Maryland and Arizona.

Polls in Nevada are open from 7:00 a.m. PT to 7:00 p.m. PT.