A tale of two parties: Trump, Mamdani put political clout on the line as four states hold primaries

New York City Mayor Zohran Mamdani and President Donald Trump are not on the ballot, but their sway over the Democratic and Republican parties will be tested Tuesday as New York, Maryland, Utah, and South Carolina hold primary elections and runoffs.

Trump, seemingly aiming to hedge his bets, made an 11th hour endorsement ahead of the South Carolina GOP gubernatorial runoff and is now backing both candidates in the showdown to succeed term-limited Republican Gov. Henry McMaster.

Meanwhile, Mamdani is testing the limits of political power as he takes on the party establishment one year after sending political shock waves across the country with his New York City Democratic primary victory en route to winning election as mayor of the nation's most populous city.

The 34-year-old socialist mayor is backing a slate of candidates in the primary, including a trio of left-wing congressional contenders who are taking on the Democratic Party's old guard.

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At the top of this list is political organizer Darializa Avila Chevalier, the Mamdani-backed primary challenger taking on Rep. Adriano Espaillat, the Congressional Hispanic Caucus chair, in New York’s 13th U.S. House District, which covers the northern third of Manhattan and a sliver of the Bronx. Chevalier, 32, says a victory on Tuesday could be the "domino" that falls and builds a "socialist power" nationwide.

The 71-year-old Espaillat, who has been in Congress for a decade, is supported by a slew of party leaders, including New York Gov. Kathy Hochul.

The mayor is also backing former New York City Comptroller Brad Lander, who ran against Mamdani last year in the crowded primary field but became one of his biggest backers. Lander is challenging incumbent Democratic Rep. Dan Goldman in the 10th Congressional District, which includes Lower Manhattan and parts of Brooklyn. Goldman's supporters include former House Speaker Nancy Pelosi.

And in New York’s 7th, which covers parts of Brooklyn and Queens, Mamdani'endorsed state Assembly Member Claire Valdez, who is battling Brooklyn Borough President Antonio Reynoso, who is backed by retiring Rep. Nydia Velazquez.

Along with the mayor, Valdez and Avila Chevalier are also members of the Democratic Socialists of America.

Valdez has said voters are looking for Democratic candidates with moral clarity on Israel, and the three congressional primary races have focused in part on anti-Israel sentiment, with Mamdani recently referring to AIPAC, a top pro-Israel lobbying group, as "monsters."

"This is the team. This is our year. It’s up to all of us to get them over the finish line," Mamdani emphasized in a social media post ahead of a rally last week with the three candidates and Sen. Bernie Sanders of Vermont, the longtime progressive champion and two-time Democratic presidential nominee runner-up.

And at the rally, Mamdani emphasized that the Democratic Party "must change."

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It's a risky bet for the mayor, which could end with Mamdani being crowned a kingmaker, or weakening his political powers.

The socialist has been a darling of the far left for a year and a half. But six months into his tenure as New York City mayor, he can also count former critics within the Democratic Party, including Hochul, as allies. And he's even earned praise from Trump.

Trump last year repeatedly claimed Mamdani was a "communist lunatic," but during an Oval Office meeting in November that grabbed plenty of national attention, the president lauded Mamdani as a "very rational person" who would do a "really good job."

Longtime Democratic strategist Joe Caiazzo told Fox News Digital, "It's crystal clear that Mamdani understands power and how to leverage it."

"He remains incredibly popular, and it appears he also understands that may not always be the case. That's why I think you see him flexing his political muscle now. It's smart politics," added Caiazzo, a veteran of the 2016 and 2020 Sanders presidential campaigns.

The candidates Mamdani's backing, including some running for state legislative offices, are mostly showcasing the mayor's platform of focusing on affordability in a city with one of the nation's highest costs of living.

Mamdani's support for the trio of congressional candidates, along with Thursday's rally with Sanders, gives Republicans, who have long cast the mayor as a radical, more ammunition to use him as a cudgel as they work to hold their razor-thin House majority in this year's midterm elections.

"Zohran Mamdani’s socialist brand is as toxic as it comes," National Republican Congressional Committee National Press Secretary Mike Marinella told Fox News Digital.

"And during a time when Democrats don’t have a leader or a message, he’s exactly the kind of bogeyman we can use against Democrats to truly show who is leading their party and the crazy policies they all support."

In South Carolina, Trump on Friday took to social media to say that he was supporting longtime state Attorney General Alan Wilson as well as Lt. Gov. Pamela Evette in the battle for the GOP gubernatorial nomination.

"I can’t hurt one of them by only Endorsing the other, so, therefore, I am going to Endorse, for Governor of South Carolina, both Pam Evette and Alan Wilson!" Trump wrote, adding: "With either one you can’t go wrong."

The endorsement of Wilson appeared to be a move by Trump to cover his bases, because Trump was already backing Evette, who is also supported by McMaster, a longtime top ally of the president.

The South Carolina runoff had been viewed as the latest test of Trump's immense grip over the GOP and the power of his endorsements in Republican nominating contests.

And his decision to back both Evette and Wilson wasn't the first time he's made dual endorsements in the same Republican race. Most famously, Trump endorsed "ERIC" in the 2022 GOP Senate primary in Missouri, where the two major candidates were Eric Schmitt and Eric Greitens. Both candidates claimed the endorsement, with Schmitt ultimately winning the nomination.

In South Carolina, Trump endorsed Evette late last month, a week and a half before the gubernatorial primary.

Evette finished on top of a crowded field of contenders in the primary election, with Wilson second. The field also included Reps. Nancy Mace and Ralph Norman, and multimillionaire businessman Rom Reddy. Since no candidate won a majority of the vote, as the top two finishers, Evette and Wilson advanced to the June 23 runoff.

Mace and Norman endorsed Wilson after failing to advance to the runoff. And Wilson was also backed — and joined on the campaign trail on the eve of the runoff by Sen. Ted Cruz, the conservative firebrand from Texas.

Mace, reacting to Trump's endorsement of both Evette and Wilson, wrote on social media, "LMAO," which is a common abbreviation for the phrase "laughing my a– off."

The runoff between Evette and Wilson turned combustible, and in last week's final debate, both candidates launched personal attacks and accused each other of lying and misrepresenting their records.

Wilson worked to contrast his tenure as attorney general with what he's argued is Evette’s largely ceremonial role as lieutenant governor. And he has spotlighted his experience as a combat veteran, prosecutor, and the state’s top law enforcement official.

Evette showcased herself as an outsider and a Trump-endorsed businesswoman, while casting Wilson as a career politician.

The power of the president's endorsement is also on the line in upstate New York, in the race to succeed retiring Republican Rep. Elise Stefanik.

Trump is backing first-time candidate Anthony Constantino, a businessman and former boxer, who is facing off against Robert Smullen, a retired Marine Corps colonel and New York assemblyman who has the backing of the state party.

Also on the primary ballot

Incumbent Rep. Jerry Nadler's decision to retire left his Manhattan district open for the first time since he was elected in 1992. Notable Democratic candidates in this crowded field include New York Assembly members Alex Bores and Micah Lasher, the late President John F. Kennedy's grandson Jack Schlossberg, and former conservative lawyer and onetime anti-Trump Republican George Conway. Nadler endorsed Lasher — a former congressional staffer.

 Meanwhile, five Democrats are facing off in the primary in New York's 17th Congressional District, in New York City's northern suburbs and exurbs, with the winner facing off against GOP Rep. Mike Lawler in a key general election race that is one of a couple dozen that will decide if Republicans hold their razor-thin House majority.

In Utah, voters will nominate candidates for Congress using a new map that created a Democratic-friendly district in Salt Lake City, which upended reelection plans of the state’s all-Republican delegation.

And in Maryland, Democratic Gov. Wes Moore faces a longshot primary challenger as he runs for re-election amid speculation that he also has his eye on a potential 2028 presidential campaign.

Fox News' Sally Persons and the Associated Press contributed to this report