51. The 50 states plus DC.
So:
States that are not Maine or Nebraska = 48
Washington DC = 1
Maine and Nebraska popular
winner of each congressional district = 5
The two senatorial votes to the
over all winner in Maine and Nebraska = 2
--------
56
I count the two bonus points in Maine and Nebraska as separate races because you could win those without winning any particular district as in the following scenario:
District 1 10 votes D, 5 votes R, 8 votes I. D wins
District 2 5 votes D, 10 votes R, 8 votes I. R wins
State wide 15 votes D, 15 votes R, 16 votes I. I wins the bonus round
So three people could win the 4 votes in Maine.
56 races.