In a state where Democrats outnumber Republicans three-to-one, Barbara Bush told Republican women from southern Prince George's County that party members should fight hard for their ticket. This time around, the wife of Vice President George Bush said, the slate included "one of the great candidates running for U.S. Senate -- we need him very, very badly."

Prince George's County Executive Lawrence J. Hogan, a Republican candidate for the Senate, was sitting next to Bush, but at the crucial moment she apparently did not recall his name, although she referred to him earlier as a "very, very good friend."

But then, in the preceeding three days Bush had attended fund-raisers for Republican candidates in several cities in Florida and Ohio, appeared on the Today Show and at a Literacy Day program at the Library of Congress and lunched with President Reagan and President Vigdis Finnbogadottir of Iceland.

In her pep talk, Bush urged 150 Republicans at the 20th anniversary luncheon of the Henson Valley Republican Women's Club to round up as many volunteers as possible because "that one extra push, that one extra day, can make a difference." She catalogued a number of recent elections where "Republican victories and defeats were determined by a handful of votes.

"If New Federalism is to work, we need people at the local level who are going to know what to do with the money: wise, honest Republicans," she said.

The 65-member Henson Valley Republican Women's Club is devoted to encouraging women to join the Republican Party, and organizing support for Republican candidates, as well as community work. "To have someone as important as Mrs. Bush recognize the fact that we are the people who support and elect the officials, and do all the nitty-gritty work . . . is really important," club president Jeanne Cangianelli said. "Everybody needs a shot in the arm. We do this year after year, and it's nice to have someone pat you on the back, and stay you're doing good."