The Republican tea-party-backed candidate in her first TV ad since winning the primary pokes fun at comments she made during a 1999 taping of a late-night talk show that she dabbled in witchcraft when she was a teenager.
In the 30-second ad that starts airing Tuesday, O'Donnell smiles at the camera and speaks over a soft piano soundtrack. "I'm nothing you've heard. I'm you."
The tea party-backed O'Donnell faces Democrat Chris Coons in November.
"It's surprising that Ms. O'Donnell, in her first television commercial, offers no solutions to the problems facing working families," said Coons campaign spokesman Daniel McElhatton. "There's no ideas here; there's no plan."
O'Donnell's comments about witchcraft were made during a taping of comedian Bill Maher's "Politically Incorrect" TV show.
"I dabbled into witchcraft. I never joined a coven," she said on the video, a clip of which hit the Internet just days after she stunned longtime congressman Mike Castle in last month's GOP primary in her third bid for Senate.
"One of my first dates with a witch was on a satanic altar, and I didn't know it. I mean, there's little blood there and stuff like that," she says. "We went to a movie and then had a little midnight picnic on a satanic altar."
In the ad, O'Donnell says, "None of us are perfect, but none of us can be happy with what we see all around us — politicians who think spending, trading favors and backroom deals are the ways to stay in office. I'll go to Washington and do what you'd do."
O'Donnell has made light of the witchcraft comments.
"How many of you didn't hang out with questionable folks in high school?" she asked fellow Republicans at a GOP picnic in southern Delaware last month.