WASHINGTON -- Gov. Wolf on Monday endorsed Katie McGinty, his former chief of  staff, in the 2016 Pennsylvania U.S. Senate race.

McGinty is competing with former Rep. Joe Sestak and Braddock Mayor John Fetterman in the Democratic primary, and so far has lined up the most establishment support. They are running to challenge Sen. Pat Toomey (R., Pa.).

Wolf's backing of McGinty is no surprise.

"Katie was one of my opponents during the primary, and I asked her to join my administration because she demonstrated that she's in politics for the right reasons. She is a 'can do' person who doesn't just talk about it, but one who works to get things done," Wolf said in comments sent out by the McGinty campaign. "She's the Senator we need in Washington, D.C. because she shares the values of hard working Pennsylvanians and will be able to deliver for them."

Minutes after the announcement, McGinty blasted out a fund-raising email with Wolf asking donors to contribute to her campaign ahead of Wednesday's third quarter deadline.

McGinty was one of three Democrats who ran against Wolf in last year's gubernatorial campaign. She became his top aide once he won.

"The governor is on track to turn Pennsylvania around, I hope to be a partner in Washington working to help him turn things around," McGinty said in the release.

Sestak released a statement that did not mention McGinty or Wolf but said "I continue to believe that serving the people iswhat public service should be all about, not about being part of a political machine."

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