Blue Dogs Top Dems' Most Valuable List

How worthless for Democrats was turncoat Rep. Parker Griffiths? To find out, Nate Silver created a formula for determining the Democrats’ MVP for the year in the House. Choosing 10 key votes, he counted how often each rep votes with the party, then adjusted the tally based on how conservative their district was. As a result, many of the most valuable Democrats are fairly conservative, with 12 of the top 25 being Blue Dogs.

But Blue Dogs also represent 8 of the 21 worst Democrats. That “least valuable” list—which you can see at FiveThirtyEight.com—shows Democrats who were loyal so rarely that they merit primary challenges. Parker Griffiths was near the top; though his district’s pretty conservative, he voted against the party on every issue. “Brief strategy memo to teabaggers,” writes Silver: “It’s not worth mounting a primary challenge to Griffith. You’ll like him. Trust me.” (More Nate Silver stories.)