WASHINGTON (Reuters) – Senator John McCain's daughter said on Sunday that Senate nominee Christine O'Donnell of Delaware, a Tea Party favorite, is "seen as a nut job."

"Christine O'Donnell is making a mockery of running for public office," Meghan McCain said of her father's fellow Republican, who recently ran an ad declaring, "I'm not a witch."

Appearing on ABC's "This Week," McCain said O'Donnell "has no real history, no real success in any kind of business."

"And what that sends to my generation is (the message that) one day, you can just wake up and run for Senate, no matter how lack of experience you have," said McCain, 26, author of the new book, "Dirty Sexy Politics."

O'Donnell stunned the Republican establishment in September when she defeated Mike Castle, a former two-term governor and longtime member of the U.S. House of Representatives, to win the Republican U.S. Senate nomination from Delaware.

O'Donnell prevailed with the help of the conservative Tea Party movement and Sarah Palin, the former Alaska governor who was John McCain's running mate in the 2008 White House race.

Meghan McCain, who became known for her online chronicle of daily life on her father's failed presidential campaign, ripped into O'Donnell's candidacy.

"It scares me for a lot of reasons, and I just know in my group of friends, it just turns people off, because she's seen as a nut job," McCain said.

O'Donnell has been the beneficiary of an anti-Washington environment fanned by the Tea Party and voter anger about weak U.S. economy. John McCain swung to the right on a number of issues this year to beat back a conservative challenger in his re-election bid in Arizona.