U.S. Rep. John Mica has represented much of Central Florida for more than two decades.

He's the front-runner to win the U.S. House District 7 seat in November, but he’ll have to face three other Republicans in Tuesday's primary election.

Mica has served on several committees in the U.S. House of Representatives, including the Oversight and Government Reform Committee — where he's fought for reforms to help veterans in the face of the Veterans Affairs controversy.

"That's been one of my priorities ... one to make sure the hospital is built, and that's long overdue," Mica said. "And also that places like Baldwin Park, our clinics — 25 percent of the homeless in Central Florida are veterans — so they're one of my top priorities."

Mica said it's his experience that sets him apart, but all three of his challengers claim Mica is part of the problem in Washington, D.C. They said it's time for a change.

David Smith, a retired member of the U.S. Marine Corps, said he decided to run for office after veterans and business owners urged him to do so.

"And that's really what we see up in Washington, D.C., with gridlock, is just a symptom of career politicians who refuse to work with each other, who refuse to cooperate," Smith said. "And the American people and the people of Central Florida suffer because of that."

Another challenger, businessman Don Oehlrich, said he's a fiscal conservative who wants to clean up the nation's capital. In a campaign ad, Oehlrich compares career politicians to dirty diapers.

"I've had enough of these dirty diapers. Have you?" Oehlrich said in the ad, shortly after he tosses a diaper into the garbage.

Kelly Shirley, a pharmacist, said he wants to reform the health care industry and wants to start that effort by repealing the Affordable Care Act.

News 13 Political Analyst Michelle Ertel said Mica is very popular among his constituents and is poised to defeat his challengers in the primary and move on to face a democratic challenger in the fall.