Yes, I was rather surprised as well. From the polling, I had thought that there was going to be a hung government at best.

But then as the hours wore on, it developed into Cameron likely needing a coalition to a straight up Tory win, with the Liberal Democrats taking the brunt of it at the polls.

Though I did see turnout was around 66% -- the last time a US election was that high, it was 1900.

http://en.wikipedia.org/wiki/Voter_turnout_in_the_United_States_presidential_elections