In several other states Tuesday night, incumbents also fared well, with Idaho Rep. Mike Simpson and Pennsylvania Rep. Bill Shuster taking down tea party challengers. The Chamber of Commerce rode to the rescue of a number of incumbents with tough races on Tuesday, running a series of supportive ads. The chamber's preferred candidates won in every case.
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And in Georgia, the GOP establishment got what it wanted by the defeat of a tea party challenger in the race to fill the seat of retiring Republican incumbent Sen. Saxby Chambliss. (Two mainstream Republicans, Rep. Jack Kingston and businessman David Perdue, face a runoff for the nomination.)
Georgia and Kentucky once presented Democrats with rare opportunities to pick off Republican seats in a year that clearly favors the GOP. Both seats now appear safer for Republicans.
Republicans also got a mainstream candidate in Oregon to take on Democratic incumbent Sen. Jeff Merkley. The GOP's candidate there, pediatric neurosurgeon Monica Wehby, has endured some negative press lately over her personal relationships, but she comes very much from the center of the GOP and not the conservative wing that dominated in 2010 and 2012.
All of Tuesday's wins for the establishment follow previous primary days that saw business-backed candidate Thom Tillis avoid a runoff to take on vulnerable Democratic incumbent Sen. Kay Hagan in North Carolina and House Speaker John Boehner easily crush a challenge in Ohio. Many other incumbents have also dismissed challengers.
And the primary season itself comes on the heels of Boehner essentially breaking the back of the tea party movement in the House by getting a budget through that avoids any new government shutdown or debt ceiling fights this year.
The GOP is now poised to add to its House majority and give itself a solid chance of picking up the six seats needed to take the Senate.
Why is all this happening?
Partly it's because the GOP learned from bitter experience in 2010 and 2012 that untested conservative insurgent candidates such as Todd Akin can cost the party its shot at a Senate majority. Things will get much harder for Republicans in 2016, both given the number of vulnerable incumbents and the nature of electorate. If they are going to get the Senate, it has to be in 2014. Even then, holding it in 2016 will be a huge challenge.
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The party also spent the early part of this year drilling into incumbents that they can't expect to just coast through primaries, especially not with the flood of unrestricted Super PAC money that can quickly swamp an unprepared sitting member of Congress.
But a good deal of the current political trend is the result of a very different fiscal and economic background from 2010 and 2012.