...the House of Representatives votes, state by state, for the President. This means that if Great Plains were a state with 1 congressperson (Democrat), that person would presumably back the Democrat. If Metropolis were a state with 31 representatives (16 Republicans and 15 Democrats) then assuming party lines hold, that's one vote for the Republicans.
Here's a chart showing how this looked before the 2010 elections:
With a few results pending, the picture has changed:
The upshot of this is that if the Electoral College result (remembering that the distribution by states will change by 2012) produces a dead heat (269-269 for example) then right now it would mean a Republican President and a Democrat Vice President (the Senate gets to vote for the Vice President in this scenario).