It was a resounding repudiation, considering that the science of gerrymandering has been brought to such a pitch of computer-aided perfection that only a handful of seats change hands in the average election. Districts are designed to be impregnable: in the last election just ten members of the outgoing Congress won by fewer than five percentage points. ~Christopher Caldwell, The Spectator

This is an important point to make and keep making as the GOP apologists try to tell you, as some did before the election, that it was perfectly normal and average to lose north of 25 seats in a sixth-year election.  Yes, it is something so perfectly normal and average that it hadn’t happened since 1974, and for reasons we all understand quite well.  If we pretend that midterm elections continued to be governed by all the same rules that they were in 1958, we might find Tuesday’s results less than remarkable, but when we realise that the rules have substantially changed to favour the incumbent party any large-scale repudiation takes on added significance. 

Consider how many seats were originally considered to be competitive at the start of the year: approximately 40, as compared with the approximately 100 in 1994.  Republicans got 52 pickups out of those 100, which is pretty good.  In terms of the percentage of the vote the Democrats got something just over half of the national vote in the House, but in terms of the number of seats won out of those considered reasonably competitive at the start of the year this election is a massive success for Democrats.  If we take the number of seats considered competitive after the summer (which, as of last week, had been increased to 73 or so), a 28-30 seat pickup by the Dems would be comparable to, if not quite as large as, the wipeout of 1994.  Either way, it was a big, big win, the kind of win that the entire apparatus of modern politics is designed to prevent.  That in and of itself makes this something remarkable to behold, as all those forces that favour entrenched and concentrated power suffered a brief setback Tuesday.