The race, pitting a candidate supported by President Donald Trump against a rare Republican critic of Israel, Rep. Thomas Massie, has become the most expensive House primary in U.S. history.
The avalanche of spending, totaling more than $34 million through Monday, according to official records, underscores the importance of an election that could oust one of the few Republican opponents of the war with Iran.
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In the final stages of his campaign leading up to Tuesday’s vote, Massey has sought to highlight the disproportionate role of pro-Israel groups, including the American Israel Public Affairs Committee (AIPAC), in the campaign.
He said the election would be a “referendum on foreign policy” and whether pro-Israel lobbies could “bully” MPs.
“The polls show I’m ahead, but they’re desperate,” Massey told ABC News on Sunday.
“That’s why they’re sending the Secretary of War to my district tomorrow. That’s why the president is losing sleep and tweeting about this. That’s why AIPAC put another $3 million into my campaign this weekend.”
President Trump has been constantly bashing Massey on social media, and in an unusual move, Defense Secretary Pete Hegseth traveled to Kentucky to campaign for Ed Gullane, a Navy SEAL veteran who is running against the congressman.
Massey has criticized the United States’ unconditional military aid to Israel and the country’s human rights abuses in Gaza and Lebanon. He has also spearheaded a push to release government files on the late sex offender Jeffrey Epstein.
money
Despite the intensity of the campaign, the candidates themselves have not raised record amounts of money.
The bulk of the spending, more than $25.8 million, came from outside groups known as super political action committees, or super PACs.
Super PACs are typically used by special interest groups to spend large sums of money to oppose or support candidates, without the constraints of legal restrictions on direct campaign contributions.
Pro-Israel groups and donors have played a central role in the large amount of funding and advertising directed at Massey.
Three PACs with ties to pro-Israel donors spent more than $15.5 million on the campaign, according to Federal Election Commission (FEC) data.
AIPAC’s elections arm, the United Democracy Project (UDP), spent more than $4.1 million.
The RJC Victory Fund, affiliated with the Republican Jewish Coalition, has raised about $3.9 million.
MAGA KY was the biggest spender with $7.5 million.
PAC’s finances are not fully disclosed. But one of the group’s top financiers is pro-Israel billionaire investor Paul Singer, who has donated $2.5 million to UDP over the past year, the largest individual contribution to the group, according to available records.
MAGA KY also received funding from Preserve America PAC, an organization associated with Israeli-American megadonor Miriam Adelson.
The financial details of Preserve America PAC remain unclear this election cycle. However, Adelson donated $106 million to a PAC in 2024 to help elect Trump as president.
President Trump has publicly acknowledged that Adelson and her late husband, Sheldon Adelson, influenced his Middle East policy.
Before the race in Kentucky’s 4th Congressional District, the most expensive House primary was the 2024 race that ousted then-Democratic Rep. Jamal Bowman, in which pro-Israel groups including AIPAC were also among the biggest spenders.
The third-most expensive primary also involved AIPAC and its pro-Israel allies, which helped defeat progressive Rep. Cori Bush in 2024.
trump factor
Beyond millions of dollars in pro-Israel spending, Massie will have to survive the wrath of another powerful force in Republican politics: Trump.
The president of the United States has largely purged members of his party who disagree with him on key issues.
Most recently, Sen. Bill Cassidy, who voted to convict President Trump after the January 6, 2021 Capitol riot, lost in the primary to a challenger backed by the US president.
Mr. Trump is actively campaigning against Mr. Massey. In a 24-hour period between Sunday and Monday, the US president made at least four social media posts calling the lawmaker “weak,” “pathetic” and “a piece of shit.”
“The worst Congressman in the long and storied history of the Republican Party is Thomas Massie,” President Trump wrote on his platform Truth Social on Monday. “He’s an obstructionist and a fool. Vote for him tomorrow, Tuesday. It’s going to be a great day for America!”
But Massie appears to have some advantages over other Republican dissidents.
Over the years, the congressman has developed a reputation as a combative and principled liberal, making him popular among right-wing commentators.
His campaign directly raised $5.5 million, significantly more than Mr. Gallein’s $3.1 million, while also receiving outside support from gun advocates and liberal PACs.
Ms. Massey also has support from her Republican colleagues, including outspoken right-wing Rep. Lauren Boebert.
And with the involvement of pro-Israel groups, Massie’s supporters say the race is not just about Trump, who remains popular among Republican voters.
“Why does President Trump hate Massey? Is this congressman a secret liberal? Absolutely not,” right-wing commentator Tucker Carlson said in a Monday newsletter.
“Unlike nearly everyone else in the Republican Party, Mr. Massie has refused to go along with abandoning the America First White House that led to his election. He is one of the few honest men in politics, and everyone who cares about our country should support him.”
