Reporting from Dover, Del. — At a Tea Party Express rally last week, Christine O'Donnell bounded onto the stage and lit up the crowd with the same fiery style that has turned Tuesday's Senate primary into another battle for the future of the Republican Party.
O'Donnell, a longtime activist who has made a career of crusading for abstinence-based sex education and other conservative issues, is now within striking distance of beating one of Delaware's best-known public figures: Rep. Michael N. Castle, the tiny state's sole representative in the House for nearly 20 years and before that its governor for two terms.
If she succeeds, O'Donnell and her conservative allies will shake up the political landscape here in much the same way Joe Miller did in Alaska and Sharron Angle did in Nevada by winning their GOP Senate primaries.
"This isn't just about my candidacy," O'Donnell told several hundred cheering supporters in Dover. "It's about changing the political system. You don't need to be part of the establishment. You don't need to be an anointed one."
Castle had seemed almost certain to cruise to victory, because his middle-of-the-road voting record had served him well for years in the Democratic-majority state. When Democratic state Atty. Gen. Beau Biden declined to run for the Senate seat once held by his father, Vice President Joe Biden, Republicans believed Castle was their best chance to take control of the seat for the first time in decades.
But the anti-incumbent mood and backlash over Obama's policies have helped ignite O'Donnell's conservative challenge. She recently won the endorsement of former Alaska Gov. Sarah Palin and a $250,000 commitment from the Tea Party Express.
The state Republican Party has gone to great lengths to push back against what it calls the out-of-town influence of the national "tea party" movement. Critics highlight O'Donnell's shortcomings as a perennial candidate who has racked up campaign debts, misstated her college degree and suggested in one interview that political opponents were following her home at night.
"Sadly, Christine's just not really a legitimate candidate in Delaware," said Republican state committee Chairman Tom Ross. "She makes a decent presentation until you know the facts."
Castle had $2.6 million in his campaign account at the end of August, miles ahead of the $20,000 that O'Donnell reported having at her disposal. But O'Donnell contends that donations have soared in recent days.
What worried Republicans in Delaware and Washington even more than the possible defeat of a major party figure is that O'Donnell could open the way to victory in November for Democratic front-runner Chris Coons. "She would lose," Ross said flatly.
Party leaders think Castle will survive the primary, but they are taking no chances, especially after Republican Sen. Lisa Murkowski lost her primary to Miller last month in Alaska. "Our challenge is just to make sure our voters take this seriously, make sure people get out the vote," Ross said.
The contrast between the O'Donnell and Castle in many ways offers a window into the changing landscape of GOP politics nationally.
Castle, a 71-year-old career politician, is among the most moderate Republicans in the House. He voted against Obama's economic stimulus and healthcare bills, but backed another signature Democratic priority, the climate change legislation in 2009.
The 41-year-old O'Donnell lived and worked in Washington for years in various capacities — as the founder of a conservative social issues organization, the Savior's Alliance for Lifting the Truth, and as spokeswoman for Concerned Women for America, an organization that works to bring biblical principles to public policy.
She ran unsuccessfully for Senate in 2006 and 2008.