WASHINGTON - The daughter of Republican hopeful Rudy Giuliani has signaled she's backing Democrat Barack Obama for president.

According to her Facebook profile, Giuliani's 17-year-old daughter, Caroline, belonged to Democrat Barack Obama's Facebook group "Barack Obama (One Million Strong for Barack)." She left the group Monday morning after the online magazine Slate sent an inquiry.

Her profile can be viewed by Facebook users who have access to New York City's Trinity School or Harvard University networks. Caroline, who is Giuliani's daughter with his second wife, Donna Hanover, recently graduated from Trinity and will attend Harvard in the fall.

Slate posted a screen shot of her profile, which uses a slightly different last name. She lists herself as having liberal political views.

Giuliani, a leading Republican candidate, has asked for privacy to deal with strained relationships in his family. Son Andrew, 21, has said their relationship became distant after Giuliani's messy divorce from the children's mother and his marriage to third wife Judith Nathan.

"There's obviously a little problem that exists between me and his wife," Andrew Giuliani told The New York Times earlier this year.

In May, Giuliani attended his daughter's high school graduation but kept a low profile, sitting in a last row balcony seat with his wife and leaving without speaking to his daughter, the New York Daily News reported.

Neither the Giuliani nor Obama campaigns had any comment on Caroline's political preference.