Alexandra and Vanessa Kerry say all the attention they're getting is taking a toll — they're a "little loopy" at this point. But it's just beginning.

On Thursday night, they're introducing their father at the Democratic National Convention (search) before he accepts his party's nomination for president.

John Kerry (search) has waged six campaigns over the past quarter-century, but this is the first in which his two daughters have worked by his side, shedding their anonymity to reach out to young voters and tell Americans about their political father's softer side.

During convention week, they've gone to delegation breakfasts, "rocked the vote" at a star-studded youth event and been interviewed live on the convention floor. They were watching from the skyboxes Tuesday night, when Sen. Edward Kennedy and their stepmother, Teresa Heinz Kerry (search), took their turns at the podium.

On Wednesday, they joined John Edwards' daughter, Cate, at a brunch hosted by people who know just what it's like to be in the spotlight: the daughters of former Vice President Al Gore.

And they're tired.

Vanessa, 27, a Harvard University medical student, joked at a breakfast meeting with reporters that she wouldn't mind having an IV to pump coffee directly into her forearm at this point.

And at a youth event, Alexandra, 30, a documentarian and actress who is working on a film about the campaign, said she and her sister were "tired and a little loopy."

Although they live on opposite coasts, the two sisters appear to be quite close, throwing an arm around each other when talking to reporters or watching events on the convention floor. They recently joked that if one stumbled on the way to the podium Thursday, they would fall down together in solidarity.

After their parents' 1982 separation and 1988 divorce, Alexandra and Vanessa lived with their mother, Julia Thorne, an intensely private woman who has since remarried and moved to Montana.

The Kerry daughters have said their father's political prominence as a senator did not affect them much.

"It's certainly starting to now as he runs for president," Vanessa told King this week, "but it's well worth it."