Hard to say, says John Sides. It sort of depends on what you mean by "mandate." And whether Republicans decide they heard the same electoral message as Democrats. I'd just add that what "the losing side" thinks matters less than what five or seven senators on the losing side think. The question is not whether the Republican leadership is cowed, but whether their ability to impose broad party discipline erodes and moderates decide that they're better off playing a constructive role in the first few years of the Obama administration. Ask yourself this: What leverage does Mitch McConnell -- whose party affiliation almost cost him reelection in Kentucky -- have on Susan Collins, who just rode her bipartisan credentials to a landslide win?
