Claire McCaskill: 'I Have Apologized' to the Clintons for 'Gratuitous and Hurtful' Remark

ABC News' Betsy Klein reports:

On the eve of her 60th birthday, Missouri Sen. Claire McCaskill said that she has officially buried the hatchet with Bill and Hillary Clinton.

McCaskill, who recently signed on to an effort to encourage Hillary Clinton to run for president in 2016, acknowledged that she was wrong to say in a 2006 "Meet the Press" appearance that "I don't want my daughter near" Bill Clinton.

"I said a lot of things in the last 30 years that I'm not particularly proud of. I mean there have been things that I've said that I wish I could take back," McCaskill said at an event in Washington, D.C. on Tuesday night sponsored by BuzzFeed. "It was gratuitous and hurtful and I have apologized to both President Clinton and Hillary Clinton for saying it."

She conceded that her decision to endorse Barack Obama in the 2008 election was controversial, but she's now thrown her support behind Hillary Clinton.

"I couldn't be more enthusiastic for her to be president now," the Missouri Democrat said in an interview with BuzzFeed's John Stanton, "and I can't wait to work as hard or harder for Hillary Clinton."

McCaskill attributed her Obama endorsement to a conversation with her children, who she said, "got in my face a little bit."

"It was impressive that my kids were able to crystallize the notion that I was worried about the implications of endorsing Barack Obama not because I didn't think he'd be a wonderful president and inspiring for our country and do something that no other candidate could do for the United States of America," she said, "but I was worried about endorsing him because of my career."

The senator said her children also inspired her to start a Twitter account, which she manages on her own.

"No one on my staff has ever tweeted one character on my account," she noted.

As one of the more prolific members of Congress on social media, McCaskill said the key to good tweets is being "multidimensional," which sometimes leads to candid encounters with her fellow members of Congress.

"I'd walk into Caucus… and [Sen. Dick] Durbin would say, 'Oh, did you have Taco Bell today?'" referring to her tendency to post on a wide range of topics.

McCaskill, whose birthday is Wednesday, posted a Spotify playlist this week titled, "Hell Yes, I'm Sixty."

A voice on social media "helps humanize all of us," she explained, and as for the attacks, "Well, there's just haters."

McCaskill also discussed the advances women have made in Congress, which she attributes to more effective fundraising.

"I was raised and taught that it was impolite to talk about money, and I found myself in a career where I'm walking up to perfect strangers… and saying, 'Give me a check with a comma.' It's a little weird," she confessed.

She spoke to a standing-room-only crowd at Jack Rose Saloon, packed with Capitol Hill staffers, journalists and other Beltway types. Sipping on her favorite Kansas City-based Boulevard Brewing Company beer, McCaskill got personal talking about what she called her "Brady Bunch" family, including three children from her first marriage, and her husband's four children from a previous marriage.

"They all are willing to tell me when they think I'm missing the point or they think I'm off base," she said. "In some ways they're like my conscience."