I'm pretty much done playing this game. For future reference, if you want people to take you seriously, you might try a little mutual respect for those who ask genuine questions. Not properly citing your sources is a form of intellectual dishonesty, and I personally am not impressed by it. Not that you seem to care, but nonetheless ...
That being said, I was finally able to reproduce pretty much the percentages you presented in your revision after much searching. Mostly I had to dig a little deeper into census.gov, and I followed a link (
http://student-voices.org/news/index.php3?NewsID=15456) posted by someone else in this thread for current registration information.
2,233,602 registered voters in 2000 cast 1,234,229 votes for President, yielding a turnout of 55.2% as a percentage of registered voters. As mentioned already, turnout as a percentage of the VAP was 48.0%
2,146,278 registered voters in 2004 cast 1,463,758 votes for President, yielding a turnout of 68.1% as a percentage of registered voters. Turnout as a percentage of the VAP was 54.9%.
What should immediately strike us is that registration in 2004 was actually
down from 2000, yet the voting age population was up. This surprised me, so I'm only just beginning to form a hypothesis about this. My initial assumption is a registration purge of those who had not voted since 1992, which is when OK voter registration was at its height. (OK law allows for occasional purges of the rolls based on participation, but I forget the exact time frame.) Voter registration in 2004 was up by 207,933 from 2002, which would indicate that voter registration went down by almost 300,000 between 2000 and 2002. That deserves further study.
In any case, the jump in the turnout as a percentage of registered voters is not particularly remarkable in and of itself, especially if the reason for the overall drop in registration from 2000 to 2004 was a result of cleaning the rolls of non-participatory voters. That would in fact explain somewhat the increase.
Anyway, thanks for starting an interesting thread. Next time, try a little cooperation with your fellow travelers.