Jenna and Barbara Bush (search), the president's rambunctious 22-year-old twin daughters, joked about being "young and irresponsible" party girls and said they were not very political but couldn't sit out their father's final campaign.

"We love our dad too much to stand back and watch from the sidelines," Barbara Bush said.

The nation got a first good look at the twins on a prime-time stage Tuesday night as they introduced President Bush, who in turn introduced wife and mom Laura Bush (search) to the Republican convention -- by satellite -- from a campaign stop in Pennsylvania.

"You make me so very proud," Bush said.

The girls, just graduated from Yale and the University of Texas, referred to hijinks that sometimes landed them in the newspaper headlines.

"We spent the last four years trying to stay out of the spotlight," Jenna Bush said to laughter from the delegates. "Sometimes we did a little better job than others." Their father once referred to his youthful drinking as a "young and irresponsible" stage of his life.

The casually dressed young women sprinkled their five-minute speech with pop culture references.

"They do know the difference between mono and Bono," Jenna Bush said of her parents. "When we tell them we're going to see OutKast (search), they know it's a band and not a bunch of misfits."

The twins followed California Gov. Arnold Schwarzenegger to the stage. They pronounced him "awesome."

Jenna joked that their appearance provided an opportunity for "payback time" on live television. Barbara confided that her parents' favorite term of endearment is "Bushie."

"We had a hamster, too," Barbara said. "Let's just say ours didn't make it." That was a reference to the revival efforts that the daughters of Democratic presidential nominee John Kerry said he performed on a family pet.

The twins' convention appearance invited comparisons with Vanessa and Alexandra Kerry, who introduced their father at the Democratic convention in July with fond remembrances and humorous stories.

The Bush daughters, recent college graduates, have recently been campaigning for their father after staying mostly out of the public eye for the first three and a half years of his term.

At the convention, they have made daily joint appearances including a short tribute to their mother at a luncheon program Tuesday.

For most of the administration, the public has seen only occasional photos of Jenna and Barbara, and the images were often unflattering. As college students, they were most in the news for extracurricular drinking.

A glamorous photo spread in Vogue this year began a transformation to more public images. The twins have traded flip-flops for strappy high heels, and except for the moment last month when Jenna Bush stuck out her tongue at photographers, they have mastered the art of the polished public smile.