As soon as Colorado's Senate race was called for Democratic Sen. Michael Bennet on Wednesday, the potential implication was apparent: Republicans had lost two Senate races they looked likely to win—Colorado and Nevada—in addition to the race they were expected to lose in Delaware. What do they have in common? In each case the Republican nominee was a Tea Party-affiliated insurgent, bolstered in the primary by national Tea Party enthusiasm over the establishment's preferred candidate. Does that mean the Tea Party cost the Republicans as many as three Senate seats?
AOL's Michael Cohen thinks so: "The harsh klieg lights of public scrutiny badly hurt Tea Party candidates. In Delaware and Nevada, Tea Party insurgents Christine O'Donnell and Sharron Angle cost the Republicans two seats that should have been easy pick-ups."
And, Politico reports that establishment Senate Republicans agree: "a bloc of prominent senators and operatives said party purists like Sarah Palin and Sen. Jim DeMint (R-S.C.) had foolishly pushed nominees too conservative to win in politically competitive states."
These statements are both somewhat true and simultaneously unprovable. Candidates such as Angle, O'Donnell, and Buck had weaknesses that may have cost them the elections. Each had at least some questionable aspects to their professional or political history: O'Donnell had made foolish statements as a young pundit, Angle had belonged to a fringe political party, and Buck had made some controversial decisions as a prosecutor. And each had extreme positions that may have been unpalatable for their state's more mainstream voters: Angle and Buck wanted to abolish the Department of Education, (Angle also had it in for the EPA), while O'Donnell's views on sexuality were retrograde. So, yes, any of those races might have gone better with a different candidate.
But it's strange that people seem so ready to assume that the GOP would have unquestionably won all those races with any old mainstream Republican as the nominee. Sue Lowden in Nevada was the party establishment's choice, and she was not so impressive herself. She was widely mocked during the primaries for suggesting that the "replace" part of the Republicans' "repeal and replace" stance on health-care reform constitute bartering chickens for medical services. Would she have been able to beat Reid, who had delivered much for the Nevada business community and reaped their support in reward? Reid could have vastly outspent her, especially if Lowden lacked Angle's access to outside Tea Party fundraising.
Colorado and Delaware seem more certain. Rep. Mike Castle (R-Dela.) is popular in Delaware and given how close the Colorado race was, it seems plausible that Lt. Governor Jane Norton might have beaten Bennet. But that sort of counterfactual history is always just a guessing game. Norton has similarly staunch right-wing views to Buck, and there is no way of knowing what dynamics might have emerged in a general election with her as the nominee, especially if she had lacked the Tea Party support that Buck brought in from out of state.
All of this must be contrasted with the overall boost that Tea Party candidates tended to get. Jonathan Sides, a political scientist at George Washington University, examined whether the Democratic vote in a contested House districts was higher or lower if the Republican was affiliated with the Tea Party, controlling for partisanship of the district, the Democrat's 2008 share of the vote, fundraising, and incumbency. His findings? "On average, the Democratic vote in districts with Tea Party Republicans was 1.3 point lower....Thus, affiliation with the Tea Party helped Republicans."
To some extent this whole debate may be moot. Tea Partiers seem chastened by their experience with O'Donnell. Tea Party Patriots staffer Keli Carender says, regarding O'Donnell: "It's great to have candidates who support Tea Party principles, but you also need candidates who can win. That's a lesson us."