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The Republican was a four-term U.S. representative, first elected in 2004. He lost his first re-election bid, but after beating colon cancer in 2008, he won the congressional seat back in 2010, pledging that he would not serve more than three terms. He lived up to that pledge, retiring from Congress in 2016.
His brother, Brian Fitzpatrick, won the seat in 2016.
"I get very emotional about my family," said Brian Fitzpatrick, who won re-election in 2018. With his brother by his side, he choked up on stage at the victory party.
"The last time there was a midterm like this, it was my brother Mike, and he came out just short. We came out on top. There were a lot of emotions, and I wanted to have him up there with me," he said that night.
Before his time in Congress, Mike Fitzpatrick was a Bucks County commissioner for 10 years.
Brian Fitzpatrick said his older brother was his hero and best friend. "Ever since I was little, I wanted to live up to him and be just like Mike in every way. He was the greatest brother and the greatest public servant our community has ever known."
U.S. Sen. Pat Toomey, R-Pa., made a public statement on Monday: "Congressman Mike Fitzpatrick served our commonwealth and country with great integrity, competence, and dignity. During his time as a Bucks County commissioner, and then as a member of Congress, Mike proved time and again that it is possible to work across the aisle to make progress while remaining true to one's principles."
Former Congressman Pat Meehan, who served in the House with Mike Fitzpatrick, said he was impressed by the way his colleague handled his cancer's recurrence. And, he noted how Mike Fitzpatrick was motivated to benefit his constituents, not himself.
Ellen Saracini reached out to Mike Fitzpatrick when her husband, Victor, pilot of United Airlines Flight 175, was killed during the 9/11 terrorist attacks.
"In D.C., Mike worked with me on legislation for a bill to install secondary barriers on all aircrafts," Saracini recalled.
That legislation, known as the Saracini Aviation Safety Act, is in effect to this day.
"He believed, as I did, that we had to close this gaping vulnerability on our flight deck so that we could never allow a repeat of terrorists breaching the cockpit again," she said.
Mike Fitzpatrick also worked to make sure all Bucks County residents who died in the attacks would be remembered, Saracini said, by getting them get a $750,000 grant to complete the Garden of Reflection in Lower Makefield Township.
"He was a great man. He was a great American," she said.
Bucks County District Attorney Matt Weintraub said his relationship with Mike Fitzpatrick spans years.
"I've known Mike since I was a young ADA, and he was a commissioner. He was somebody I sought to emulate in all of my years in public service," Weintraub said.
He said Mike Fitzpatrick's ability to work with so many different people is one of the main reasons he was able to win and serve four terms in Congress.
"He was an exceptional public servant. It didn't matter what your affiliation was, whether you were rich or poor, which part of the county you came from. He always strove to treat everybody the same," he said.
Weintraub said he's going to miss Mike Fitzpatrick — the man, not just the politician.
The Fitzpatrick family said he died of melanoma, peacefully, and surrounded by family. He leaves behind his wife and six children.