Democrats don’t like to think about Republicans if they can help it. But for those on the left now contemplating their own “progressive tea party” movement, they’d do well to contemplate one woman in particular: Christine O’Donnell.
In 2010 Republicans had an unusual opportunity to win the deep-blue Delaware Senate seat once held by Joe Biden. The vessel: GOP Rep. Mike Castle, a popular former governor and the front-runner. Enter Ms. O’Donnell. Fueled by tea-party enthusiasm and money, she trashed Mr. Castle as a liberal and beat him in the primary. After a general election that devolved into debates over gay service members, religion, creationism (and even witchcraft), Democrat Chris Coons blew out Ms. O’Donnell by 17 points.
The conservative tea-party phenomenon is overall one of the more successful political movements in modern American history. Even the left acknowledges it now. Still, every movement makes mistakes. The tea party—especially in its early years, and given its decentralized nature—has had its share, including Ms. O’Donnell.