Josh Marshall's instincts here are, I think, spot on. Marshall is puzzling through why speaker John Boehner (R-OH) is still hunting for a "grand bargain" now rather than passing the middle class tax cuts and waiting for the debt ceiling negotiations when he'll have "more leverage". His theory, and mine, is that Boehner knows he won't actually have more leverage at that point.
John Boehner may have been part of the original Contract with America, but he's been in Washington through the 1995 shutdown and the 2011 near shutdown. Both dealt substantial damage to the Republican party brand; Clinton coasted to reelection as the economy recovered and he could effectively tar Republicans as the anti-government party; and Republicans got a net negative 50 approval rating for their handling of 2011 debt ceiling negotiations. Congress is always unpopular, but most of the time a large chunk of the public just doesn't have an opinion on them one way or another. During the last debt ceiling fight, Republicans were just terribly unpopular, and if they stick to their no-taxes-evar guns to the point where National Parks close and hospitals start receiving IOUs, they'll be unpopular again. So if House Republicans threaten to jump off the debt ceiling cliff, Obama should let them unless they're willing to meet the President more than halfway. After lengthy negotiations where he appears to be the adult in the room, of course.