FILE PHOTO: Election staff work in the Clark County Election Center in North Las Vegas

2022 Nevada Primary Election Results

LAS VEGAS (AP) — Republicans in Nevada were deciding Tuesday between a candidate with a political pedigree and former President Donald Trump’s backing and a political newcomer as their choice to try to unseat one of the most vulnerable Democratic senators in the country this fall.

The primary race was originally expected to be a cakewalk for Adam Laxalt, one of Nevada’s most prominent Republicans who has already won statewide office and attracted support from both Trump and Senate Republican leader Mitch McConnell.

Yet in the final weeks before Tuesday’s U.S. Senate primary, Nevada’s former attorney general faced a surprisingly spirited challenge from Sam Brown. A retired Army captain and Purple Heart recipient, Brown has appeared before swelling crowds drawn to his profile as a political outsider. He bolstered his campaign with strong fundraising numbers, particularly among small-dollar donors who often represent the party’s grassroots.

WATCH: Breaking down the primary results and what they mean for midterm elections

Long lines kept some polling places open in Clark County, where about three-quarters of the state’s population lives, after polls were officially slated to close at 7 p.m. local time.

Across the country in South Carolina, Rep. Tom Rice, one of 10 Republicans who supported Trump’s second impeachment, lost his South Carolina primary Tuesday in another sign of Trump’s enduring hold on his party. The former president endorsed Rice’s rival, state Rep. Russell Fry, and traveled to the district earlier this year to support Fry.

But much of the attention Tuesday was on Nevada, where the winner in a GOP Senate contest would go on to face Democratic Sen. Catherine Cortez Masto in what may be the GOP’s best opportunity to flip a Senate seat and regain control of the chamber.

Despite the intrigue surrounding the race, many Republicans still see Laxalt as best positioned to win the nomination, in no small part because of Trump’s backing.

“President Trump is the most popular Republican official in America by a long shot,” said Corry Bliss, a Republican strategist who works on campaigns around the U.S. “If you have his endorsement and you have resources to advertise that, you should win.”

Republicans in Nevada were also choosing a nominee to challenge Democratic Gov. Steve Sisolak. Elsewhere, Republicans in South Carolina were weighing whether to support two U.S. House members who have crossed Trump. And two longtime rivals in Maine were poised to advance to what will likely be one of the most competitive governor’s races in the U.S. this fall.

Still, Nevada’s Senate race is the highest-profile contest Tuesday.

Laxalt is well-known in the state for having served for four years as Nevada’s attorney general and campaigned unsuccessfully for governor in 2018. He’s also the grandson of former U.S. Sen. Paul Laxalt.

And perhaps most importantly in GOP circles, he’s got ties to Trump. Laxalt worked on Trump’s reelection campaign and promoted his lies about election fraud in the state after the 2020 election. Trump in turn hosted Laxalt for a fundraiser at his Mar-a-Lago club in Palm Beach, Florida, and appeared in a campaign ad for Laxalt.

But the party’s anti-establishment base has muscled behind Brown, who was badly burned by an improvised explosive device in Afghanistan and has highlighted his personal story in his outsider crusade.

“I wasn’t born into power,” Brown declared in a recent campaign ad in which he recounted how he nearly died in Afghanistan. He then smiles, saying, “It turns out I’m hard to kill.”

Brown, to the surprise of many in the state, won the endorsement of the Nevada Republican Party at a convention vote in late April and a straw poll of the Las Vegas-area GOP at a May gathering. Recent polls have shown him closing in on Laxalt, though the state, with a transient population and many late-shift workers due to the state’s tourism and casino industry, is considered fickle for pollsters.

Though Laxalt is still considered the favorite to win, both candidates are expected to have a similar chance in November at defeating Cortez Masto, who is expected to handily win her party’s endorsement over several little-known competitors.

“I imagine that Laxalt would be a stronger candidate in the general than Brown, but I don’t think it’s a substantial difference,” said Kenneth Miller, an assistant professor of political science at the University of Nevada, Las Vegas.

That’s because Cortez Masto, the first Latina elected to the Senate and successor of the late Sen. Harry Reid, is considered one of the most vulnerable Democrats running for reelection this year.

Democrats broadly are facing headwinds this year, burdened by an unpopular president and rising costs. In Nevada, high prices for gas are acutely felt by residents of Las Vegas’ sprawling suburbs or those commuting from far-flung rural areas.

Those same factors could imperil the reelection of Sisolak, whose Republican challenger will emerge from Tuesday’s primary.

In the Nevada governor’s race, Clark County Sheriff Joe Lombardo is considered the favorite in a crowded field and has earned the coveted endorsement from Trump.

The former president notably snubbed another Republican candidate in the race, former U.S. Sen. Dean Heller, who was once a critic of Trump’s and earned a public scolding from the then-president.

Also challenging Lombardo is Joey Gilbert, a northern Nevada lawyer and former professional boxer who was outside the U.S. Capitol when it was stormed on Jan. 6, 2021. Like Brown in the Senate race, Gilbert has picked up support from the party’s base.

Trump’s false claims of fraud in the 2020 election are laced throughout some of Tuesday’s contests, including what’s normally a little-watched race for Nevada secretary of state. Republican Barbara Cegavske, who was censured by the Nevada GOP for declaring there was no fraud and defending the results as accurate, is term-limited. A crowded field of Republicans who have embraced “election integrity” concerns to varying degrees are vying to replace her.

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