Sean Parnell is a U.S. Army combat veteran and congressional candidate for Pennsylvania’s 17th district in the upcoming election. He is campaigning on a pro-veteran, pro-military platform.

He is expected to deliver a speech on Monday, the first night of the Republican National Convention.

In an opinion piece titled “How an Afghanistan veteran went from broken to featured Republican convention speaker” published in the Washington Examiner Friday, Parnell detailed how he failed Ranger School the first time around, was deployed to the Middle East, and was eventually out-processed from the U.S. Army 10 years ago after completing rehabilitation for a traumatic brain injury.

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He said his speech at the RNC will be about “bringing people together. It's about unity. It's about leadership. The theme is that we united on the battlefield in the 3rd Platoon with people from all walks of life in the face of certain death.

"One of the most profound leadership lessons that we learned over there was we did not let our differences divide us. We learned very quickly that we all bleed red. If you focus on our differences, we would probably die, so we put that aside. We united as Americans, and we fought on, and because of that, we were victorious," he continued.

Parnell is said to be one of President Trump’s favorite candidates in the 2020 race, with the president labeling him an “American hero” on Twitter. Also a New York Times best-selling author, Parnell said Trump famously called him out by name during a speech at the Shale Insights Conference in Pittsburgh, challenging him to run for office.

He will oppose Rep. Conor Lamb, who spoke at the Democratic convention last week. Parnell, who is vying for the seat in the suburban western Pennsylvania district beginning six miles outside of Pittsburgh and stretching northwest to Beaver and Butler counties, is also the co-founder of American Warrior Initiative, a veteran advocacy group.

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In a political ad released in June, Parnell said he is “old enough to remember when the House of Representatives functioned as a legislative body. Not a Trump derangement syndrome support group.”

He criticized his opponent, Lamb, for his voting record, including to impeach Trump, against the Born Alive Act, for the Paris Climate Accords, for having an “F” rating from the NRA and for voting with House Speaker Nancy Pelosi 90% of the time. Parnell said Pelosi fails to represent the people of western Pennsylvania and stays in power because of her “socialism squad in the House,” a reference to freshman Democratic Reps. Alexandria Ocasio-Cortez, Ayanna Pressley, Rashida Tlaib and Ilhan Omar.

“Conor became Pelosi’s little lamb the moment he got to Washington,” Parnell tells the camera. “Lamb supports Joe Biden who wants to put AOC in charge of Pennsylvania’s energy jobs. That’s like putting Bill Clinton in charge of your intern program.”

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In the final line of the ad, Parnel concludes: “Let’s send a lion to Congress, and not a lamb.”

He is not to be confused with the former Republican Governor of Alaska, also named Sean Parnell.