The Pennsylvania primary is May 17.By Jon Delano

PITTSBURGH (KDKA) — When local candidate Sean Parnell dropped out of the race for U.S. Senate last week, it seemed to open the field to many other candidates.

One of those candidates was Dr. Mehmet Oz, who announced on Tuesday.

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When Republican U.S. Sen. Pat Toomey announced he was retiring at the end of next year, Republican insiders knew the battle to replace him would be long, contentious and expensive.

What was not predicted was how many newcomers to politics and, frankly, recent residents of other states would seek to represent Pennsylvania.

There’s already been lots of talk about Oz, who was born in Ohio, raised in Delaware and lived in New Jersey for most of his adult life until he recently rented a home near his in-laws in the Philadelphia suburbs.

But Oz is not alone.

Long-time Californian Carla Sands, President Donald Trump’s ambassador to Denmark — she gave $250,000 to the Trump campaign — has returned to Pennsylvania where she was born and grew up so she can run for the U.S. Senate.

And then there’s Dave McCormick, former CEO of Pittsburgh-based Free Markets who was born in Washington County and grew up in the state but now lives in Connecticut running a hedge fund. McCormick is expected to return to Pittsburgh soon to announce his candidacy for the Senate.

None of these three has held elective office, and all three Republicans are multi-millionaires who can self-fund their primary races.

Political analyst Larry Ceisler told KDKA political editor Jon Delano that all this was “unprecedented.”

“It’s like unprecedented. Basically, to joke about it, we haven’t seen such an invasion in Pennsylvania since Lee came to Gettysburg,” Ceisler said. “It’s not so much people coming in from out of state and seeing opportunity. But what about the potential candidates who are from Pennsylvania?”

“Half of our congressional delegation is Republican, and you have to wonder why don’t they want to run?” Ceisler said.

Of course, there are other Republican candidates in the race, including former Lt. Gov. candidate Jeff Bartos and former congressional candidate Kathy Barnette. And former U.S. Rep. Keith Rothfus is likely to announce his candidacy soon.

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Bottom line: The candidacy of Oz has certainly not stopped others from making a run for the same office.

“The race has certainly changed from a few weeks ago, and it seems like every day the race becomes more open,” Ceisler said.

“When you have as many people running as you apparently have running now and no apparent leaders to clear the field, it’s reasonable to assume that a lot of other people are going to be looking around,” said Dave Ball, chair of the Washington County Republican Party.

Local Republican county chairs are not surprised at all the candidates, but differ about Oz’s impact, especially since he just moved to Pennsylvania from New Jersey.

“I do think the celebrity of Mehmet Oz is a significant factor,” said Al Lindsay, chair of the Butler County Republican Party.

“I do think it creates a blind spot in the general election if our nominee didn’t really have ties to Pennsylvania,” said Jim Christiana, chair of the Beaver County Republican Party.

Oz did go to school at the University of Pennsylvania and married a Philadelphian, and Sands and McCormick, although native Pennsylvanians, moved back to the state to run for Senate.

“I don’t think you can really call Dave McCormick an out-of-stater. He’s a Pennsylvanian. He was born in Washington,” Ball said.

Whether the carpet bagger label actually sticks to any candidate remains to be seen, but it is unusual to see so many out-of-state Republicans, whatever their roots in Pennsylvania, move back here to run for Senate.

It’s a sign of how much this seat is up for grabs.

So far, the four major Democratic candidates are all elected Pennsylvania officials, including Montgomery County commissioner Val Arkoosh, Lt. Gov. John Fetterman, state Rep. Malcolm Kenyatta and U.S. Rep. Conor Lamb.

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The Pennsylvania primary is May 17.