On Wednesday night at a steakhouse in Washington, Obama met with Rubin and a number of supporters including Michael Froman of Citigroup, Brian Mathis of Provident Group, Orin Kramer of Boston Provident Partners LP (who committed to Obama shortly afterwards) and Robert Wolf, the chairman of UBS Americas.

Rubin is the son of Clinton Treasury Secretary Robert Rubin. For obvious reasons, he would be a nice get for the Obama campaign -- both a prominent name and a positive statement about Obama's generational appeal rolled into one.

Rubin's allegiance is still uncertain -- he did not return phone calls to his home and office -- but according to a supporter with knowledge of the meeting, he seemed inclined to commit to Obama.

--Jason Horowitz