Republican presidential candidate, Wisconsin Gov. Scott Walker speaks in Washington on June 20, 2015. (AP Photo/Jacquelyn Martin, File)

The Ricketts family sweepstakes are over and Scott Walker has won handily, according to Republicans familiar with Unintimidated, the super PAC supporting the Wisconsin governor and presidential candidate.

Federal election filings will soon show that billionaire investor Joe Ricketts and his wife, Marlene, have together given $5 million to the Walker-allied group — a significant haul from one of the GOP’s biggest donors.

Their son, Todd, is another Walker donor and co-chairman of his national fundraising efforts. In recent months he has hosted events for the governor and traveled with him on the campaign trail.

Federal filings will also show donations to other GOP contenders, including former Florida governor Jeb Bush, Sen. Marco Rubio (Fla.), New Jersey Gov. Chris Christie, Sen. Ted Cruz (Tex.), and Sen. Lindsey O. Graham (S.C.), among others. But Walker’s take far exceeds his rivals, Republicans said.

Joe Ricketts, the family patriarch, settled on Walker after private meetings over the past year at his New York apartment and his ranch in Wyoming’s Jackson Hole valley. They bonded over their Midwestern backgrounds and conservative views on spending, associates said.

The Ricketts family, which owns the Chicago Cubs, has quickly become one of the more active clans in American politics.

Joe Ricketts, 74, founded TD Ameritrade and in 2010 launched his own super PAC, Ending Spending (now run by Todd). That group spent millions supporting Republicans in 2012 and did the same during the 2014 midterm elections.

Laura Ricketts, daughter of Joe and Marlene, is one of the Democratic Party’s mega-donors. Pete Ricketts, one of the couple's three sons, was elected governor of Nebraska last year.

Unintimidated, the Walker super PAC that can collect and spend unlimited amounts of money, is named after Walker’s 2013 autobiography, “Unintimidated: A Governor’s Story and a Nation’s Challenge.” It announced this month that it has raised about $20 million from nearly 300 donors. Keith Gilkes, a longtime Walker adviser, is its director.