Tea Partier Christine O'Donnell Wins in Delaware

Another huge message from the tea party and potential bad news for Republicans: Christine O'Donnell defeated the GOP establishment candidate, longtime congressman Mike Castle, in Delaware's Senate primary, reports Politico (whose headline begins "GOP Nightmare ..."). She won 53% to 47%. "Don't ever underestimate the power of 'we the people,'" she said in her victory speech, later giving out a shout of thanks to Palin ("You Betcha!") and a nod of recognition to Glenn Beck's 9/12 project.

At one point, her supporters began a chant of "Yes we can." In his concession speech, Castle did not mention his opponent, and he took no questions about whether he'd endorse her. O'Donnell had the backing of Sarah Palin, along with the enmity of many Republicans who fear she's going to lose in November to Democrat Chris Coons. Her win could in fact reduce Republican chances of retaking the Senate, as Nate Silver spelled out today in his FiveThirtyEight blog. (More primaries stories.)