Virginia voters who turn out for the state's first presidential primary election next week on "Super Tuesday" will encounter a ballot that differs somewhat from those of past elections.

Rather than having a single ballot that includes both Democratic and Republican candidates, Virginia has prepared a separate, color-coded ballot for each party. Voters must choose between the two before entering the voting booth.

The separate ballots make it possible for state and party officials to determine who votes in each of the party contests. The national Democratic Party does not allow primaries in states where Republicans can surreptitiously cross over and vote, possibly weakening the Democratic field.

Republican ballots will be white and Democratic ballots will be blue. Each will contain all the names of the party's presidential candidates, plus a box marked "uncommitted." Write-in votes will not be allowed.

As always, voters will indicate their choice of candidates by secret ballot. Although it will be possible to learn which party a person selected, it will not be possible to determine whom a person voted for.

Most of the other details associated with voting will remain the same as in past years. The customary polling places will be open in all the state's precincts. The usual hours, 6 a.m. to 7 p.m., will remain in effect.

The results of the primary will have a concrete effect on the Democratic presidential battle, but the GOP race is a nonbinding "beauty contest." Virginia Democrats will send 85 delegates to their party's national convention, and 75 of them will be allocated on the basis of the primary results. After Tuesday's vote, Democrats will hold conventions for voters in the 10 congressional districts. Each district will chose its delegates at that time based on the primary vote.

For state Republicans, the primary will serve only as an indication of the candidates' statewide popularity. Virginia's 50 delegates to the national convention will be chosen at conventions in each of the state's 10 congressional districts and at the statewide convention in June.