David McCormick, who is expected to announce his candidacy for Pennsylvania's open Senate seat soon, is already gaining some critical supporters.

McCormick is the CEO of Bridgewater Associates, one of the largest hedge funds in the world, and the former Under Secretary of the Treasury for International Affairs under President George W. Bush. He is expected to formally announce his candidacy for the primary election taking place on May 17, 2022. Although no announcement has been made, he has garnered support from influential Pennsylvanians.

Longtime Republican national committeewoman Christine Toretti and former state party chair Rob Gleason have already endorsed McCormick. Fundraisers Pat Deon and Bill Sasso also are among his backers.

"He's a salt of the earth guy who served his country and worked hard," Deon said in a text message. "He can relate to someone who wears a hard hat or sits in a boardroom."

The Republican primary field to replace Senator Pat Toomey is expected to be a crowded one upon McCormick's official announcement. Dr. Mehmet Oz recently announced his plans to run for the seat, despite not being a Pennsylvania resident. Conservative activist Kathy Barnette, investor Jeff Bartos and former Danish Ambassador Carla Sands are also running.

The presidential battleground is a big electoral prize that backed Democrat Joe Biden in last year's election and Trump in 2016.

Democrats have a strong primary field with far more electoral experience.

They include John Fetterman, the state's lieutenant governor, third-term U.S. Representative Conor Lamb of suburban Pittsburgh, state Representative Malcolm Kenyatta of Philadelphia and Val Arkoosh, a former chair of anesthesiology at Drexel University College of Medicine who chairs the three-member board of commissioners in Montgomery County.

For the Republican candidates, the rubber may begin to meet the road on January 15, when the state party's central caucus will hold closed-door candidate interviews. Other regional caucuses will follow, leading up to the state party endorsement meeting on February 5.

McCormick has avoided media, other than speaking with a conservative-friendly columnist, and has been meeting Republican officials in private meetings arranged by Toretti and other backers.

He is spending more than $1 million out of his own pocket to air a Christmas-themed TV ad across Pennsylvania this week and has filed paperwork with the IRS that allows him to start raising money for his candidacy before he formally declares, a campaign adviser said.

McCormick has lived in Connecticut since 2009. To re-establish residency, the Pennsylvania native bought a house in Pittsburgh's East End, near where he lived two decades ago before leaving in 2005 to serve in Bush's administration.

He is married to Dina Powell, a veteran of the Bush administration and Republican National Committee who also was a deputy national security adviser to Trump before she returned to work at investment bank Goldman Sachs. That has helped give McCormick an introduction to Trump's circle.

Wealthy, connected candidates—McCormick, Oz and Sands—moving from blue states in pursuit of a Senate seat in purple Pennsylvania has fast become an issue in the campaign.

McCormick's backers tip-toe around that by stressing his growing up in Pennsylvania, graduating from high school in Bloomsburg where he still owns a family Christmas tree farm, and spending about a decade in business in Pittsburgh, where he ran online auction house FreeMarkets Inc.

Some Republicans know McCormick through his father, who was the first chancellor of the state university system under then-Governor Dick Thornburgh.

After high school, McCormick went to West Point, served in the Gulf War and got a doctorate at Princeton University before he headed into business in Pittsburgh, first as a consultant at McKinsey and Co.

He had insisted on going to McKinsey's Pittsburgh office, he said on SiriusXM's Leadership Matters radio show in 2020, because he had "imagined that I might try to do something political and thought that coming back to Pennsylvania, I'd be able to figure that out."

He was a registered Democrat at the time but found the local party hard to get involved with and instead ended up volunteering on a Republican candidates' countywide race, which began his transition to becoming a Republican, he said.

He held three positions in Bush's administration, departing after serving as the Treasury Department's under secretary for international affairs.

The Associated Press contributed to this report.

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