CQ Politics did a post-primary assessment of the 2010 House races and has moved the seats of seven Democratic incumbents into the ‘Lean Republican’ column. See if you can detect a pattern:

Colorado 4th — Rep. Betsy Markey (elected ‘08)

Florida 24th — Rep. Suzanne M. Kosmas (elected ‘08)

Illinois 11th — Rep. Debbie Halvorson (elected ‘08)

Maryland 1st — Rep. Frank Kratovil Jr.(elected ‘08)

Ohio 1st — Rep. Steve Driehaus (elected ‘08)

Ohio 15th — Rep. Mary Jo Kilroy (elected ‘08)

And finally there is…

Texas 17th — Rep. Chet Edwards (elected ‘90) — Which CQ calls “without a doubt, the most difficult rating change to make.” More on Edwards here.