ABC News’ Devin Dwyer reports: Christine O’Donnell, the Sarah Palin and Tea Party backed candidate, dealt a stunning blow to the Republican establishment Tuesday night, defeating the moderate, party-favorite veteran Rep. Mike Castle in the Delaware GOP senate primary.
“Don’t ever underestimate the power of we the people. We the people will have our voice heard in Washington once again," a jubilant O'Donnell told her supporters at a rally in Dover.
With 100 percent of precincts reporting, O’Donnell won 53.1 percent of the vote to Castle’s 46.9 percent.
“The last several weeks have been spirited, shall we say,” said Castle in a speech after the results came in. “The voters in the Republican primary have spoken and I respect that decision.”
Castle is the eighth GOP establishment-backed candidate to be upset in a primary challenge this year.
His loss immediately casts doubt on GOP chances of winning the senate seat, which had been hed by Democrat Joe Biden for 36 years, and could close the door on a Republican effort to gain control of the Senate in November.
Unlike Alaska, where conservative lawyer Joe Miller shocked Republicans by defeating sitting Sen. Lisa Murkowski in last month's primary, Delaware is a heavily Democratic state and recent polls have shown O’Donnell would face a much more difficult race against Democrat Chris Coons than would Castle.
Castle is a pro-abortion rights, pro-gun control Republican who has a popular reputation of reaching across the aisle to work with Democrats. He has served two terms as governor of Delaware and nine terms in the U.S. House.
O’Donnell, a former marketing consultant who failed in two previous bids for elected office, ran on a more conservative platform with backing from the Tea Party Express.
"I have no doubt if she by some miracle became the nominee she would lose the seat by unprecedented numbers," Delaware Republican Party chairman Tom Ross said last week.
Now Ross and national party leaders, who have spent weeks trashing O’Donnell, face the decision of whether to go to bat for her in the race against Coons.
The executive director of the National Republican Senatorial Committee, Rob Jesmer, only offered a muted response to O’Donnell’s victory: “We congratulate Christine O’Donnell for her nomination this evening after a hard-fought primary campaign in Delaware.”
O'Donnell tonight appealed to party leaders to unite around her in the campaign ahead. "A lot of people have already said that we can’t win the general election," she said. "They are the same so-called experts that said we had no chance of winning the primary. It will be hard work but we can win. If those same people that worked against me will work just as hard for me, we will win.”