McCormick and Casey Win Senate Primaries, Setting Up Battle in Pennsylvania

David McCormick won an unopposed Republican primary for Senate in Pennsylvania on Tuesday, according to The Associated Press, securing the party’s nomination two years after former President Donald J. Trump torpedoed his first Senate run by backing his primary rival, the celebrity physician Dr. Mehmet Oz.

Mr. McCormick will face Senator Bob Casey in the November election. Mr. Casey, the Democratic incumbent, also won his uncontested primary on Tuesday, The A.P. reported.

The Senate race in Pennsylvania, a key battleground state, represents the best chance yet for Republicans to unseat Mr. Casey, an 18-year incumbent who has previously sailed to re-election — he defeated his Republican opponent in 2018 by 13 points.

Mr. McCormick, the former chief executive of Bridgewater Associates, one of the world’s largest hedge funds, is part of a roster of wealthy Republican Senate candidates recruited to run in 2024. He and his wife, Dina Powell McCormick, a former Trump administration official, reported assets in 2022 worth $116 million to $290 million.

Mr. Casey, the son of former Gov. Robert P. Casey, was catapulted onto the national political stage in 2006, when he defeated Rick Santorum, then one of the most powerful conservatives in the Senate, in a closely watched campaign.

Mr. Casey has moved considerably to the left during his Senate career. He once called for the overturning of the constitutional right to an abortion enshrined in Roe v. Wade. After the Supreme Court dismantled Roe in 2022, Mr. Casey supported bills aimed at ensuring access to abortion. Mr. Casey was also once an opponent of many gun control measures, but he re-evaluated his position after the mass shooting in 2012 at Sandy Hook Elementary School in Newtown, Conn., less than 100 miles from the Pennsylvania border.

Mr. McCormick narrowly lost a chance to run against the Democrat John Fetterman for Pennsylvania’s other Senate seat in 2022, when he was defeated by Dr. Oz in the Republican primary by fewer than a thousand votes. Mr. McCormick and Dr. Oz had fought bitterly for the support of Mr. Trump in that primary, and Mr. McCormick had pointed to Dr. Oz’s Turkish American heritage and his Muslim faith as reasons not to back him.

But Dr. Oz ultimately won Mr. Trump’s endorsement. In Mr. McCormick’s telling, in a memoir published last year, the former president threw his support behind Dr. Oz after Mr. McCormick refused to back Mr. Trump’s lie that the 2020 election was stolen from him.

For a race that hung on a knife’s edge, Mr. Trump’s intervention in the primary proved decisive. Mr. Trump unleashed a series of broadsides against Mr. McCormick, and rallied at Dr. Oz’s side even as many of Mr. Trump’s supporters were unenthusiastic about the former president’s favored candidate. The former president said that Mr. McCormick was “not MAGA,” and called him “the candidate of special interests and globalists and the Washington establishment.”

Mr. McCormick and allies attacked Dr. Oz as a “Hollywood liberal.” During a debate, he pointedly jabbed at Dr. Oz’s television past: “The problem, doctor, is there’s no miracle cure for flip-flopping, and Pennsylvanians are seeing right through your phoniness, and that’s what you’re dealing with and that’s why you’re not taking off in the polls.”

Other candidates attacked both Mr. McCormick and Dr. Oz as out-of-state carpetbaggers. Dr. Oz had lived most of his adult life in New York and New Jersey and had only recently changed his voting address to his in-laws’ home in the Philadelphia suburbs. Even in his second run for Senate, Mr. McCormick has split his time between the campaign trail and a $16 million mansion in Westport, Conn.

With Mr. McCormick running unopposed in the Republican primary on Tuesday, Mr. Trump has endorsed him for the impending battle against Mr. Casey.

Democrats have already begun recycling attacks that Mr. Trump wielded against Mr. McCormick, as well other lines of attack concerning his wealth, his residency in Connecticut and his misleading claims made in an effort to portray himself as a rural Pennsylvanian of humble origins.