Download (10k) C++ and Java source for Borda, Condorcet, Raw Rated and Acceptance voting.
Aside from using the code to write your own things, there's a wrapper program that reads voting data of a certain format and tallies it. From the man page:
vote reads in files of either rankings or ratings, integer or float, text or binary, and processes that data with one of several election methods. The winner or winners in the case of a tie are printed. The general format of a file read by vote is:If "number of choices" is specified on the commands line, it must not be in the file.