ORLANDO, Fla.--"Stand up for America" is the slogan, and they came last night to stand up and sing and shout and dance for America, because Alabama Governor George C. Wallace had just swept to an overwhelming victory in the Florida Democratic primary.

With 87 per cent of the vote tabulated, Wallace had 43 per cent. His nearest competitor, Minnesota Senator Hubert H. Humphrey, tallied 17 per cent of the vote, scoring strongly in Florida's black districts. Senator Henry M. Jackson of Washington finished third with 14 per cent, while Maine Senator Edmund S. Muskie finished a poor fourth with only 9 per cent.

Wallace has probably swept all twelve Congressional districts, giving him all 81 of Florida's delegates to the Democratic National Convention.

Wallace election night headquarters in the Grenada Room of the Park Plaza Hotel here was bedlam last night. Bedecked in Wallace hats, Wallace neckties, and Wallace skirts and sports jackets, a crowd of several hundred cheered each new report of a Wallace victory. Announcements of returns in counties in the northern Florida panhandle, where Wallace received between 65 and 75 per cent of the vote, were greeted with yells and dancing.

"The abstract issue in this campaign was the distance of the government from the average citizen," Wallace told the crowd in the packed ballroom at 10:30 p.m. "This is a victory for the average citizen of the country."

Wallace added that victory in Florida, with a population made up of people who come from many states, "proves my candidacy is national, not regional."

The Wallace victory here was much greater than anyone had predicted, and the results of this primary could throw the race for the Democratic nomination into a shambles. Wallace's victory makes him a viable national candidate.

Busing

In an important side issue a proposal for a Constitutional amendment to prohibit busing received nearly 75 per cent of the vote.