Delaware GOP Senate nominee Christine O'Donnell said Thursday she regrets making a campaign ad that addressed her past involvement with witchcraft, saying it backfired. 

O'Donnell, a conservative activist who pulled a stunning upset of nine-term centrist Rep. Mike Castle in the state's Senate GOP primary, said that her intention was to "kill" the chatter among the political class about her past controversial statements.

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"Yeah, yeah — you know I haven't publicly stated this and I don't know if I will get in trouble for saying that, but our intention was to kill it. And that's not what happened," she said on ABC's "Good Morning America."

Democrats have pounced on O'Donnell's past statements about sexuality and masturbation to paint her as an extreme candidate who is out of touch with Delaware voters. 

During an appearance on Bill Maher's "Politically Incorrect" in the 1990s, O'Donnell said that she had "dabbled" in witchcraft at a younger age.

O'Donnell's ad released early this month sought to break down those perceptions. "I'm not a witch, I'm nothing you've heard. I'm you," she says in the 30-second spot.  

But the ad continued talk of her past and was lampooned by "Saturday Night Live."

The Republican nominee trails Democrat Chris CoonsChris Andrew CoonsBiden threatens more sanctions on Ethiopia, Eritrea over Tigray conflict Senate Democrats to Garland: 'It's time to end the federal death penalty' Hillicon Valley: Cryptocurrency amendment blocked in Senate | Dems press Facebook over suspension of researchers' accounts | Thousands push back against Apple plan to scan US iPhones for child sexual abuse images MORE, the New Castle County executive, by double digits in the race for Vice President Joe BidenJoe BidenHouse clears bill to provide veterans with cost-of-living adjustment On The Money — Dems dare GOP to vote for shutdown, default To reduce poverty, stop burdening the poor: What Joe Manchin gets wrong about the child tax credit MORE's old Senate seat.

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