Why Republicans Will Keep the House

At Politico, Alex Isenstadt explains why Republicans will keep their majority in the House -- and even have an outside chance to enlarge it.

• Obama: "Unlike in 2008, when Barack Obama’s national numbers helped lift up Democratic congressional candidates across the map, the president has had far less impact this time around. And for the Democrats in conservative districts in the South and Rust Belt, Obama’s presence on the ballot has been more hurt than help."
• Money: "Between July 1 and Oct. 31, the NRCC and allied outside groups outspent their Democratic counterparts $168 million to $131 million."
• Medicare: "Democrats credit Republicans — some of whom had been initially concerned about Ryan’s impact on down-ballot candidates — with launching a vigorous pushback on the issue, accusing Obama of including cuts to Medicare in his health care bill. By the time October was up, a Kaiser Family Foundation poll found Mitt Romney leading Obama on the question of who’s more likely to protect Medicare."
• Redistricting:  "That wide-ranging power allowed Republicans to strengthen districts for their majority. When the redistricting dust settled, 109 Republican seats were made safer, compared with 67 Democratic seats. Once-vulnerable Republicans like Pennsylvania Reps. Jim Gerlach and Patrick Meehan found themselves in easier districts."
• Retirements: "Throughout 2011, and into the opening months of 2012, Democrats watched in horror as 27 incumbents announced they were calling it quits."
• Map Shrinkage: "Democrats essentially ceded the South and only succeeded in competing in a smattering of seats in Ohio, Pennsylvania and New Jersey. In other words, the party gave up on a pretty big swath of the country."
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