The fight for Congress had almost everything the presidential contest lacked. Not necessarily public excitement: the low turnout in the presidential race also held down the numbers of voters who pulled levers for House and Senate candidates. But certainly closeness, unpredictability, even down-to-the-wire, nail-biting suspense. So many races looked so even so late in the campaign that as the voting began, pundits were hedging even more blatantly than usual. Either party, they proclaimed, could wind up king of Capitol Hill--and by either a tiny or a huge margin.
Yet in the end not much changed. Republicans kept control of both the...