WASHINGTON -- President Barack Obama and Vice President Biden endorsed Katie McGinty in Pennsylvania's U.S. Senate race Wednesday, drawing two of the biggest names in Democratic politics into their party's April 26 primary.

"Katie is a true champion for working families, with a proven record of taking on big challenges and delivering for people," Obama said in a statement released by the McGinty campaign. He cited her work with Wolf to use the Affordable Care Act to expand Medicaid coverage to more than 500,000 Pennsylvanians.

Her two main opponents, Joe Sestak and Braddock Mayor John Fetterman, both expressed disappointment in the news, though each said they still support the president.

The endorsement capped off a raft of big-name support for McGinty, Gov. Wolf's former chief-of-staff. The Wayne resident is running second to Sestak in public polling, but hoping for a big push to the finish line.

Biden added, "Pennsylvania is near and dear to my heart, and there is no one better to represent its working men and women in the Senate than Katie McGinty." Citing her blue collar background in Philadelphia -- daughter of a restaurant hostess and a police officer -- he said, "she knows what it means to work hard, struggle to make ends meet, and build a better life, one day at a time."

McGinty is competing with Sestak, a former admiral and congressman, Fetterman and western Pennsylvania spring manufacturer Joseph Vodvarka for the Democratic nomination in a race that could help determine control of the Senate.

UPDATED: Fetterman, in a meeting with the Inquirer's editorial board, said he was "hurt" and "profoundly disappointed" after he endorsed Obama in 2008, even when most Democrats in Pennsylvania backed Hillary Clinton.

"That's the sad reality about establishment politics. I wonder now how establishment Obama would treat candidate Obama in terms of that, and it really stung," Fetterman said. "I was really his only friend in Western Pennsylvania. Eight years later, it wasn't there … I'm not angry, I'm more sad because this is a person who I still think is a fabulous president."

Sestak, in a news release, said he and the president share common ground on many issues, such as immigration, national defense and health care. "We wear the same battle scars, with pride," Sestak said.

McGinty has yet to make a dent in public polls, but says she has momentum as top Democrats make her their choice to take on Sen. Pat Toomey (R., Pa.) in a key contest this fall. A barrage of TV ads backing McGinty are expected from outside political groups in the coming weeks.

The Republican Senate campaign arm called the endorsements a "last ditch effort to prop up her campaign" and said Democrats are worried because Sestak leads in polling but "can't beat Pat Toomey."

Obama also endorse Sestak's 2010 primary rival, the late-Sen. Arlen Specter. Sestak won that race but narrowly lost to Toomey in the general election.

McGinty, in her release, said she is "honored" to have support from Obama and Biden.

"I proudly share their commitment to building an economy that works for all Pennsylvanians and fighting to strengthen the middle class," she said.

She has previously been endorsed by Sen. Bob Casey (D., Pa.) and a host of other top Democrats and labor unions.

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