Retirement season is upon the House, and so far the numbers are pretty even: there are 13 Democratic open seats and 15 GOP open seats, although there could be 10-20 more before the cycle is over. The good news for Democrats is that just two of their 13 open seats are at serious risk of falling to Republicans, while five of Republicans' 15 open seats are at risk of falling to Democrats. Nonetheless, Senate bids by Democratic Reps. Ann Kirkpatrick (AZ-01) and Patrick Murphy (FL-18) complicate Democrats' path to significant gains in the House, because are two of just five House Democrats sitting in seats won by Mitt Romney in 2012. In both seats, Democrats are counting on messy late August Republican primaries to help them hold on. Elsewhere, virtually all the action is in Democratic primaries. AZ-01: OPEN (Kirkpatrick) (D) - Northeast: Flagstaff, Navajo Nation, Casa Grande Toss Up. Kirkpatrick owes her 2014 reelection to a late GOP primary that produced a very weak opponent. Her decision to run for Senate makes this one of Republicans' best pickup opportunities

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