RICHMOND, JAN. 20 -- Attorney General Mary Sue Terry has decided to endorse Sen. Albert Gore Jr. (D-Tenn.) for president, and will campaign for Gore in Virginia and throughout the South, according to sources close to Terry.

Terry, the first statewide Virginia Democrat to endorse any of the would-be nominees, is expected to be named a national cochairman of the Gore campaign, the sources said.

"Obviously we are tremendously excited about her endorsement," said a member of Gore's campaign staff. He said Gore and Terry will appear together at a news conference Saturday at Gore headquarters in Crystal City.

Gore has made two trips to Richmond in recent weeks, most recently meeting with Terry and Gov. Gerald L. Baliles on Jan. 10.

Baliles and Lt. Gov. L. Douglas Wilder, both Democrats, have said they plan to stay neutral in the presidential sweepstakes, at least until after Virginia's first-ever presidential primary on March 8.

A Terry spokesman said that the current session of the Virginia General Assembly, which ends March 12, "will be a limiting factor" in Terry's participation in Gore's campaign before Super Tuesday on March 8.

"But she will do some traveling" for Gore at night and on weekends, according to the spokesman.

Observers said Terry's decision to back a presidential candidate, while politically risky, will raise her profile and might be interpreted as a prelude to her own possible announcement this spring that she will be a candidate for governor next year.

Terry and Wilder are considered the leading candidates for the Democratic nomination. The lieutenant governor is hosting a pair of fund-raisers in Richmond on Saturday, including a $1,000 a couple dinner.