It helped drive Republican fervor to an a historic pickup of at least 60 seats in the House, but also may have cost the party a firm grip on Congress as a whole – and could yet do the same to a Republican bid for the White House in 2012.
"Ultimately, it's impossible to know exactly how things would have played out had the Tea Party movement not existed," writes Brian Montopoli at the CBS News website. "But it certainly appears that the nomination of both O'Donnell and Angle cost the Republican Party."
Senate races, of course, have a different dynamic than House races. With most states having several – and in some cases dozens – of House races, those races play out on a much smaller scale and often in districts that have been gerrymandered to favor one party. But Senate races, contested statewide, more frequently tend to reward more moderate candidates.
Moreover, on the House side, the rallying cry of "Fire Pelosi" – the successful bid to remove Rep. Nancy Pelosi from her position as Speaker – might have proven more compelling than the bid to oust Senator Reid.