2008:
64,206,511 - Obama
56,611,357 - McCain
= 120,817,868
http://news.yahoo.com/election/2008/dashboard
2004:
62,040,610 - Bush
59,028,444 - Kerry
=121,069,054
http://en.wikipedia.org/wiki/United_States_presidential_election,_2004
I’m not sure where you got your numbers, but they are wrong.
The numbers for 2008 are estimates. The numbers quoted by Yahoo! and Fox News and others do not yet include all absentee ballots.
The final tally won’t be known for a bit yet, but the national voter turnout is expected to be about 62%.