Joe Trippi told us before the election that a superior ground game could be worth 2-3% at the polls to a presidential campaign. TechPresident's Nancy Scola called that estimate "more art than science," which seemed fair enough at the time.

Now Nate Silver of the groundbreaking number-crunching site FiveThirtyEight.com works the forumlae and says, "So the rule of thumb that a 'good' ground game may be worth additional 2-3 points above and beyond what is reflected in the polls appears to hold; a great ground game may be worth somewhat more than that."

More here soon from Silver.