Two top donors to President Obama's super-PAC are now helping out one that supports Hillary ClintonHillary Diane Rodham ClintonMueller moves ahead with Papadopoulos sentencing What's wrong with the Democratic Party? Just look at California BBC: Ukraine paid Cohen 0K to set up talks with Trump MORE for president.

Steve and Amber Mostyn have signed on as founding members of Ready for Hillary's national finance council. The two combined to donate more than $5 million to Democrats in the last election, including $3 million to the pro-Obama Priorities USA.

The Mostyns are top Texas-based trial lawyers. Joining them on the group's finance council is Susie Tompkins Buell, the co-founder of the Esprit clothing company. The longtime Democratic activist is a friend of Hillary Clinton's who served as her San Francisco fundraising chairwoman in 2008.

"Ready for Hillary is the wisest investment right now for anyone who wants Hillary Clinton to be the next president," Buell said in a statement provided by the group. "Its founders are innovative and dedicated; they are building a massive grassroots movement of Hillary supporters across all 50 states to show Hillary how ready the nation is for her to be president. It is powerful and essential work. It is building a movement of millions of Americans from the ground up. I am proud to join this team."

The group's announcement is the latest sign the group is getting key institutional support and could be a major player should Clinton decide to run for president. Others helping the group include former Clinton White House Political Director Craig Smith, former Rep. Ellen Tauscher (D-Calif.) and Harold Ickes, a senior adviser on Hillary Clinton's 2008 presidential run. Former Michigan Gov. Jennifer Granholm (D) and EMILY's List founder Ellen Malcolm are also involved.