The underdogs are having their day, so far, in Delaware and New Hampshire.
Based on early returns, Republican Senate candidates Christine O'Donnell and Ovide Lamontagne are leading their establishment-backed rivals.
O'Donnell leads 55 - 47 percent with 37 percent of precincts reporting over Congressman Mike Castle, the centrist former two-term governor who has been considered the frontrunner to win VP Joe Biden's former seat since last year. Castle won the endorsement of the Delaware GOP and is supported by the National Republican Senatorial Committee.
Lamontagne leads 52 - 32 percent with 7 percent of precincts reporting over former state Attorney General Kelly Ayotte, recruited to run for this seat by the NRSC.
Both candidates have outsider credentials, though both have run for office before. O'Donnell is a conservative media commentator, not an elected officials; she's also been described as a "perennial candidate" and ran for the same seat in 2008 (against Biden). Lamontagne is currently a lawyer; he was also the GOP's gubernatorial nominee in 1996 and served on the state board of education.
Both have been endorsed by conservative Sen. Jim DeMint, who has set out to back more conservative Senate candidates this election cycle. So far, he's getting his way. An O'Donnell win would be considered a coup for Sarah Palin, who also endorsed her, and for Tea Party Express, which is financially backing her campaign through statewide independently-run TV ads knocking Castle and praising O'Donnell.
Election results via Politico.
Chris Good is a political reporter for ABC News. He was previously an associate editor at The Atlantic and a reporter for The Hill.