Pre-12th amendment, each elector had TWO votes.
but the two votes were undesignated -- in effect, though not in intent, they were BOTH votes for President. Now, you cast one vote labelled as for a Pres, and one for a Vice-Pres. Thus, GW could only have gotten a maxiumum of one-half of the votes cast, which he did (unless you could cast both votes for him, which you couldn't).