They called it the Democratic traveling road show.

They squeezed the party's top eight Virginia leaders and a pack of reporters into three tiny planes today and hopscotched across the state, dodging thunderstorms and issuing brash boasts of party unity. It was the Democrats way of taunting their Republican opponents on the eve of the GOP's state convention.

And for Democratic Gov. Charles S. Robb, who suffered through the party's disastrous 1984 presidential and state Senate campaigns, it was a chance to put his political prestige behind three Democratic candidates with winning political records.

"We did it to get a jump on the Republicans," said Lt. Gov. Richard J. Davis, who gave up his own bid for the Democratic gubernatorial nomination several weeks ago in the name of party unity. "It shows we have got a running head start."

Despite engine problems on one plane and faulty wing flaps that grounded another, the politicians and reporters bounced across the state from Norfolk to Richmond and from Dulles International Airport to Blacksburg.

At each stop there was a carefully staged news conference with plenty of words like "dedicated" and "experienced" and "competent" heaped on each of the three candidates for statewide office in the fall elections, usually leaving little time for questions from reporters.

The candidates danced around the controversial issues and sidestepped any that may have threatened their quest for party unity.

The Democratic ticket, however, is likely to be as controversial as any assembled by the Virginia Democratic Party. Leading the cast is Attorney General Gerald L. Baliles, who is unopposed for the gubernatorial nomination. State Sen. L. Douglas Wilder of Richmond is the party's only candidate for lieutenant governor and state Del. Mary Sue Terry of Patrick County is seeking the attorney general slot.

To Republican critics who have called the ticket too liberal for Virginia, Wilder responded: "Our campaign won't be one involved in labels. There are those who want to drag out labels, but we won't argue those. We'll be arguing issues."

Above all, this was a chance for party leaders to capitalize on the success, the popularity and the glamor that surrounds Robb, son-in-law of the late president Lyndon B. Johnson.

"We're not gonna lose the campaign if he stays home and we're not gonna win just because he comes out," said State Sen. Joseph V. Gartlan (D-Fairfax), one of two dozen Northern Virginia officials who greeted the entourage at Dulles. "But if he pitches in and actually campaigns for the whole ticket, he can do a great deal."

Robb seemed to relish the role yesterday. He played emcee and cheerleader all in one breath.

He even spoke candidly of some of his own shortcomings.

Explaining why he was unable to pick out some local officials in the small but enthusiastic partisan crowds at each stop, he declared: "I'm both blind and vain," a reference to his weak eyes and his distaste for wearing eyeglasses in public.

The day wasn't without its shots at the Republican Party.

Trying to appeal to supporters from Northern Virginia, the populous area that will be crucial to the election of statewide candidates, Baliles struck out at Republican gubernatorial candidate Wyatt B. Durrette, a former Fairfax County legislator who now practices law in Richmond. "Durrette left here after he declared you couldn't be from Northern Virginia and run successfully for state office," said Baliles.

Even while campaigning for his colleagues, Robb was coy about assessing his own political future. His four-year term ends in mid-January and under Virginia law he cannot succeed himself.

"I don't have any present intentions for running for any elective office," Robb said, wincing at the noise in his ears as the six-seater plane roared down toward the Dulles runway. He added quickly: "It may change."