FILE: Crowds rush in and run out of the Chesapeake Bay as they participate in the 17th Annual MSP Polar Bear Plunge at Sandy Point State Park on Saturday, January 26, 2013. (Tracy A. Woodward)

Maryland state lawmakers have plenty to disagree about during this year’s legislative session, but one cause will unite them on Saturday: the annual Polar Bear Plunge in the Chesapeake Bay.

Two Democrats and one Republican from the House of Delegates plan to test their courage in the bone-chilling event at Sandy Point State Park, helping to raise money and awareness for the Special Olympics.

The participating lawmakers are Dels. Herbert H. McMillan (R-Anne Arundel), Aruna Miller (D-Montgomery) and C.T. Wilson (D-Charles), and they’ve had no shortage of encouragement from other members in recent weeks.

On Friday, House Speaker Michael E. Busch (D-Anne Arundel) waved a $100 check from his podium during floor proceedings, promising to donate the money to whichever lawmaker could hold his or her breath the longest underwater. He promised another $100 to whoever could break a record he jokingly fabricated.

“The record is three minutes and 21 seconds,” he said, establishing a mark that would be impossible for most people to meet. “Good luck to you.”

McMillan, a former Navy pilot, and Wilson, an ex-Army Special Forces member, will have more than party pride at stake as they uphold the long-standing Army-Navy rivalry with some friendly competition in the frigid Chesapeake waters.

McMillan already has a fundraising edge over his colleague, having collected about $3,000 in donations compared with roughly $1,000 for Wilson. But fundraising is only part of the challenge, as the lawmakers still have to take the plunge.

“I don’t think it’s all that bad,” said McMillan, who will be participating in the event for a sixth consecutive year. “This year is probably going to be colder than some, but I usually go in a couple of times. The best way to get ready is not to think about it.”

Wilson said he expects Saturday’s dip to be difficult, despite his experience with grueling Special Forces training.

“I did my thing in the military in my 20s, but now I’m 43,” he said. “It’s going to be a challenge.”

Wilson added that he views the event as an opportunity for lawmakers from both parties to unite around a common cause.

“We had a tough start with overriding the governor’s vetoes at the start of session, so this is something to kind of mend bridges and get things on an even stride,” he said. “We have to work together.”

Saturday’s forecast calls for clear skies and a high temperature of 45 degrees.

Gov. Larry Hogan (R) attended a separate Polar Bear Plunge on Friday for Maryland State Police. He handed out an award but did not enter the water.