One of the enthusiastically supported issues at the Democratic midterm convention four years ago in Memphis was the proposed constitutional amendment to extend full voting rights to residents of the District of Columbia. But now, with the amendment as moribund as the one seeking equal rights for women, the issue of expanding the franchise of residents of the nation's capital was barely mentioned at this year's conference.

Participants perfunctorily reaffirmed their support for the voting rights amendment, which has been ratified by only 10 of the needed 38 states, but they heard nothing of the newer drive for statehood for "New Columbia." The only mention of statehood concerned Puerto Rico.

Theodis R. Gay, chairman of the 26-member D.C. delegation here this weekend, said it was premature to ask conference participants to support the proposal before Washingtonians have voted on whether they want statehood.

So with the exception of "Last Colony" buttons worn by John Hechinger and others in the city delegation, the drive to expand the franchise of D.C. residents was limited to the all-but-hopeless cause of getting two senators and one or two representatives by amending the constitution.

Mayor Marion Barry didn't show up, so the closest thing to politicking in the upcoming mayoral election was the presence of buttons worn by partisans--most notably the buttons touting Barry's rival, Patricia Robert Harris, worn by Sharon P. Dixon, the national committeewomam and wife of Council Chairman Arrington Dixon.

Virginia was a conspicious island of calm in the midst of the enthusiastic reception given to a speech by Sen. Edward M. Kennedy today. As multicolored confetti showered down all around them, the Old Dominion participants, except for a few from the Washington suburbs, maintained a polite but stony silence.

National Committeewoman Lousie Cunningham, from Lynchburg, was on her feet applauding, but she denied that her reaction implied support for Kennedy.

"He's the only one I know I'm not supporting," she said. "But he does give a good speech." As for her colleagues in the delegation, she said, "I feel fairly confident that Virginia will not go for Kennedy."

The Virginians played it cool with the presidential aspirants. "You listen to them, you clap for them and you make up your mind later," explained state party chairman Alan Diamonstein of Newport News.

It wasn't easy to stand out in a crowd here, with so many famous faces, unless you are as tall as Tom McMillen, the former All-American basketball player at College Park.

At 6 feet 11 inches, McMillen is--by half a foot over New Jersey Sen. Bill Bradley--the world's tallest former Rhodes Scholar-turned professional basketball player-turned politician, and if the pace of McMillen's activity at the conference here is any gauge, he may be one of the hardest-running noncandidates. McMillen's head towered above the crowds at parties and dinners, disappearing just long enough to stoop when he shook hands.

In addition to maintaining a home in Atlanta, where he plays basketball with the Hawks, McMillen has one in Crofton in Anne Arundel County, and that has led to speculation that a natural target for his first venture into elective politics might come two years from now, against conservative Republican Rep. Marjorie S. Holt.

McMillen has become friends with national party chairman Charles T. Manatt, who singled out McMillen for an introduction at the governors' luncheon. And just in case anyone doesn't know the name of the prematurely gray giant patrolling the corridors here, his political sidekick, Frank Bolling, is there to introduce him.

Former Maryland senator Joseph Tydings, who appears to be serving as something of a patron to McMillen, also has adopted the presidential candidacy of Colorado Sen. Gary Hart. What began as a small gathering for Marylanders developed into what Tydings correctly described as "another one of these parties for a couple hundred of my closest and dearest friends."

Speaking of crowds, the D.C. delegation threw a party Friday night that attracted so many late-night partygoers that it was impossible to do much more than shake hands with Del. Walter E. Fauntroy and delegation chairman Gay as the mob surged through the suite, with a brief stop at the bar, and then back into the hall.

"There were just a few hundred more than we expected," said Gay as a reporter squeezed past. The reason the D.C. event was so popular was that it began at just about the time the huge bash thrown by Kennedy ended. Delegates swarmed out of La Bourse--Philadelphia's version of the Georgetown Park intown mall--boarded waiting chartered buses, and headed for the next party.