WASHINGTON - The nation's capital rolled out the red carpet - and holiday garlands - yesterday for music stars like Alan Jackson and Katharine McPhee, who performed for President Bush and the first lady at the annual "Christmas in Washington" concert.

TV host "Dr. Phil" McGraw and his wife, Robin, hosted the festivities for the fourth time. The event, at the National Building Museum, benefited Children's National Medical Center.

"This event is one of the season's great traditions," Bush said. "After all, when else can you see a world-class tenor, country-music legend and Dr. Phil all in the same place?"

The president thanked the members of the military, calling them "one of our greatest blessings."

"Many are spending this Christmas far from their homes, but they are close in our thoughts and our prayers, and so are the families who support them," Bush said.

Internet sensation Colbie Caillat sang "I'll be Home for Christmas" and joined R&B singer-songwriter Ne-Yo for a duet of "Silent Night." Tenor Andrea Bocelli performed "Adeste Fideles," and "American Idol" runner-up McPhee took over the tune to sing "O Come All Ye Faithful."

"High School Musical" star Vanessa Hudgens performed "The Christmas Song (Chestnuts Roasting on an Open Fire)," and Tony-winner Heather Headley sang "Have Yourself a Merry Little Christmas." Country-music legend Jackson performed his own holiday song, "Let It Be Christmas."

The president and first lady joined the performers on stage for the final number, "Hark, the Herald Angels Sing."

The concert will air Wednesday night on Turner Network Television. *