Democrats in districts that went for Bush in 2004 or McCain in 2008 may suspect that President Obama, with his often detached and enigmatic style, wouldn’t necessarily miss them all that much if they were to lose in 2010.

With a Republican takeover, Obama — far from repeating Bill Clinton’s reaction to his congressional reproof in 1994 — could go the other way, becoming a far better progressive purist and liberal icon, unwilling to compromise his redistributive beliefs in the face of reactionary opposition. With a defiant Obama at the progressive barricades, gridlock might save him from himself — and, importantly, set up an uncompromising post-presidential persona that would make the globe-trotting careers of Tony Blair, Bill Clinton, Jimmy Carter, and Al Gore look amateur. Such considerations, I think, terrify stodgy centrist Democrats up for reelection this fall.