Charles Franklin, of the University of Wisconsin, has a nice chart on pollster.com on registered voters and likely voters. It presents trend estimates of the Obama/McCain margin among all polls, adults, likely voters, and registered voters. By comparing the trend lines of likely voters and registered voters, we can track the balance of enthusiasm, about which I wrote recently. The trend lines suggest that, contrary to my guess, McCain did distinctly better with LVs than RVs from February through May, that Obama did better in June, and that McCain has been doing better since mid-July. Obama does better among all adults than among RVs from January until about the time the Reverend Wright tapes surfaced March 13, but since he clinched the nomination June 3, he has done about equally well among all adults and RVs. What all this suggests to me is that the Obama campaign's organizational efforts are definitely worthwhile, while such efforts matter less to McCain, whose supporters seem more likely to vote.