The Hotline's Tim Sahd has some updated House race rankings at National Journal. Check out the 30 most competitive congressional races across the country, and what makes them so competitive, now that Democrats have preserved the late Rep. John Murtha's seat in Pennsylvania and the latest round of House primaries, held on Tuesday night, are behind us.

Top 5:

1. Tennessee 6th district, open seat (D)
2. Louisiana 2nd district, Rep. Joseph Cao (R)
3. Louisiana 3rd district, open seat (D)
4. Delaware at-large district, open seat (R)
5. New York 29th district, open/special election (D)