A key reason Democrats remain in a strong position to retain the House majority is the disparity in open seats: roughly three times as many Republicans (27) are retiring or running for other office as Democrats. Of Democrats' ten open seats, only one is at risk of GOP takeover: retiring Rep. Dave Loebsack's IA-02. And even there, Democrats have a reasonable chance to hold the seat.

However, there are fierce primaries underway for several safe seats outgoing Democrats are leaving behind, including those of Senate candidates Reps. Joe Kennedy (MA-04) and Ben Ray Lujan (NM-03). And strangely, the biggest ideological clash may be playing out in the bluest seat in the nation, that of retiring Bronx Rep. Jose Serrano (NY-15). Here's a quick look at where these ten races stand.

Updated Bottom Lines

CA-53: OPEN (Davis) (D) - Central San Diego, La Mesa, Lemon Grove Solid Democratic. This suburban San Diego district was purple when Rep. Susan Davis captured it in 2000 but is now so blue that in the wake of her retirement, two Democrats advanced to November from

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