By any measure, Obama’s willingness to negotiate for hours on end is remarkable, said Ross K. Baker, a Rutgers University political scientist who studies Congress closely.

“Usually, not too much ink gets on a president’s fingers,” Baker said. “But he’s rolled up his sleeves. He gave the framing job to Congress, and he’s doing the finishing work now.”…

A congressional aide who attended Wednesday’s marathon session said Obama rarely left his chair, where he was flanked by House Speaker Nancy Pelosi and Majority Leader Steny Hoyer. Senate Majority Leader Harry Reid and other senators sat across from them. Key staffers such as White House Chief of Staff Rahm Emanuel took the other seats.