As one of the world's largest motorcycle rallies rolls into the American capital this weekend, one person will be hoping the rumble of hundreds of thousands of bikes will draw even more attention to his presidential run.

Presumptive Republican presidential nominee Donald Trump will be in Washington on Sunday to lend his support for the annual Rolling Thunder motorcycle ride.

Trump is scheduled to speak at the event, according to Bloomberg Politics, which first reported on his plans.

"I am doing it in honor of the great bikers who have been totally supportive of my campaign, and now I want to be supportive of them," Trump said in a statement. "I look forward to it!"

Motorcycle enthusiasts have frequently attended Trump campaign rallies to show their support for the candidate they believe is different from career politicians whom they accuse of degrading the military and ignoring veterans.

Participants get ready for the Rolling Thunder 'Ri FILE - Participants get ready for the Rolling Thunder 'Ride for Freedom,' May 25, 2014. (Dimitris Manis/VOA) FILE - Participants get ready for the Rolling Thunder 'Ride for Freedom,' May 25, 2014. (Dimitris Manis/VOA)

The bikers have shown support despite Trump's remarks last year that disparaged one of America's most famous prisoners of war, Senator John McCain.

'Not a war hero'

“I don’t like losers,” Trump said at the Iowa Family Leadership meeting in July 2015. At the same event, when asked about McCain, who was described by the questioner as a “war hero,” Trump responded, “He’s not a war hero.”

He went on: “He’s a war hero because he was captured. I like people that weren’t captured, OK?”

McCain, a U.S. Navy pilot, was a prisoner of war for nearly six years in Vietnam after being shot down during a mission.

Rolling Thunder, which has been held annually since 1988, is a tribute to prisoners of war and Americans missing in action, just like McCain was.

Ray Manzo, a former Marine corporal, is one of the men credited with organizing the event. A letter from Manzo was published in Outlaw Biker magazine in 1987, calling for riders to descend on Washington the Sunday before Memorial Day.

Participants drive toward the Lincoln Memorial the FILE - Participants drive toward the Lincoln Memorial the Rolling Thunder 'Ride for Freedom' in Washington, May 25, 2014. (Brian Allen/VOA) FILE - Participants drive toward the Lincoln Memorial the Rolling Thunder 'Ride for Freedom' in Washington, May 25, 2014. (Brian Allen/VOA)

Nearly 3,000 riders came for that first ride. The organization says the event has now grown to more than 1 million riders and spectators combined.

Broader purpose

The group's mission has grown alongside the ride. The organization lobbied for the Missing Service Personnel Act of 1993, which prohibits the Pentagon from declaring a service member killed in action without substantial evidence.

It has also set up a nonprofit organization that provides thousands of dollars' worth of aid to veterans’ families every year. According to the philanthropy analyst Guidestar, the charity gave away more than 90 percent of its funds in 2014.

But on Sunday, politics and philanthropy will take the back seat for a few hours as hundreds of thousands of bikes, vintage to modern, American and foreign, will gather in the Pentagon parking lot and wait for Defense Secretary Ash Carter to announce the start of the 2016 ride.

They will ride across the Memorial Bridge, past the U.S. Capitol and end at the Vietnam Veterans Memorial in a not-so-silent tribute to their fallen and missing brothers and sisters in arms.