You can only throw your vote away on the presidential vote.
Where does the electoral college come in? When you vote for
federal senators and representatives. Vote for (as best
one can) the better guy among them. The popular presidential
vote is used only for stuff like: major party status, and
federal election funding. So, vote for people you like for
president even if they can't get elected, it's good for them.
Somewhere I found a site that polled you on your views on
a bunch of topics and figured out which presidential candidate
was closest to you (and showed you a comparison to all the
candidates, including some withdrawn ones). I'll see if I
can find it.
Sorry to rant, blue. This whole campaign year's
driving me mad with the stupidity of others (not you)