How many Senate seats did the Tea Parties cost the Republicans?

If you ask a member of the tea parties how many senate seats their candidates lost the GOP, they'll probably say "-17". However, from this:

The Fix looked at Angle, Buck, O'Donnell and two other faces of the tea party: New York governor candidate Carl Paladino and Kentucky Senate candidate Rand Paul.

The five of them, it turns out, ran behind the vast majority of other Republican candidates -- and sometimes by wide margins.

In almost every case, they ran behind more mainstream Republican candidates for governor, lieutenant governor, secretary of state and other statewide offices. And in no case did the tea party candidate run significantly ahead of another statewide Republican candidate...

...Among House candidates, Iraq veteran Jesse Kelly, who lost to Rep. Gabrielle Giffords (D-Ariz.), state Sen. Brad Zaun, who lost to Rep. Leonard Boswell (D-Iowa), and even state Rep. Raul Labrador, who beat Rep. Walt Minnick (D-Idaho), all fared less well in their districts than other Republican candidates running for office in the state.

Chris Cillizza includes the disclaimer that those races were higher-profile than the down-ballot ones, but that would seem to make his case even stronger: few people probably have a burning interest in who's going to be the treasurer of Nevada and the results above would seem to indicate that even many Republicans couldn't stand those listed above.