ON TUESDAY Virginia will elect a new legislature. Much is at stake, and Northern Virginians who care about schools, traffic and other issues at least partially within the purview of state government would do well to pay attention.

National parties and political figures certainly have been paying attention, because Tuesday's vote could dramatically shift the balance of power in Richmond. Republicans already control the state's top three positions -- governor, lieutenant governor and attorney general -- and, narrowly, the state Senate. With a shift of only one seat, the Republicans could win control of the House of Delegates, too. That could put them in a commanding position for a decade, since this General Assembly will be redrawing state and federal legislative district lines.

In Virginia there is no typical Democrat or typical Republican. But broad differences between the parties certainly exist. Democrats tend to be more supportive of gun control, Republicans of the rights of gun owners. Republicans have been more enthusiastic about statewide standards and testing in public schools, Democrats more skeptical. Democrats tend to be more willing to spend money on schools and perceived social needs, Republicans more concerned with limiting expenditures. Given such differences, many voters may choose to vote a party line -- may decide that the importance of party control in the House or Senate overrides any distinctions between individual candidates.

On the other hand, Northern Virginia has been favored in the past with a delegation that worked well across party and jurisdictional lines. Partisan differences have taken a back seat to a shared understanding of the need for more roads, more mass transit and more and better schools. Political advertising during the campaign has exaggerated and distorted the differences, especially in the area of gun control. But there are well-qualified candidates in both parties who seem likely to continue the tradition of regional cooperation.

Jane H. Woods, senator from the 34th District in central Fairfax County, is one such candidate. A former public school teacher, Sen. Woods is a Republican who has stood up to Republican Gov. James Gilmore when appropriate, has worked well with members of both parties and has served Fairfax ably as chair of the Education and Health Committee. Her Democratic opponent, Leslie L. Byrne, is also well qualified, with experience in Congress and the Virginia House of Delegates, but her slashing campaign against the incumbent has not made the case.

Linda T. "Toddy" Puller, Democratic candidate for an open Senate seat in the 36th District in southeast Fairfax, also deserves support in a hard-fought contest. For eight years, Del. Puller has represented part of this district as a member of the House of Delegates; her record on education and transportation and her history of building coalitions within and among regions merit a promotion.

In other Senate races, able incumbents deserve continued support. These include Richard L. Saslaw in Fairfax's 35th District and Charles Colgan in Prince William County's District 29. In the three innermost districts that span Alexandria, Arlington and pieces of Fairfax County, three incumbent Democrats deserve to be reelected: Patricia Ticer, a former mayor of Alexandria, in the 30th; Mary Margaret Whipple, a former Arlington County Board chairman, in the 31st; and Janet D. Howell in the 32nd. Republican Whitney Adams, challenging Ms. Howell, is a former federal prosecutor and U.S. Civil Rights Commission staffer who has run an interesting campaign with an emphasis on traffic and making the Virginia Department of Transportation more responsive. As a first-time candidate, though, she has not made the case to replace Ms. Howell.

A couple of challengers for delegate seats have established credibility by virtue of their experience and well-thought-out platforms. James E. Mitchell III, a Democrat making his second run against incumbent Del. Roger J. McClure in District 67 of western Fairfax County, has sensible ideas to address school overcrowding and road congestion. His opponent, Del. McClure, embarrassed his district by failing to pay federal taxes owed of more than $100,000. He compounded the problem this year when several associates, including a conservative and powerful downstate legislator and several others whom Del. McClure will not name, agreed to help guarantee a loan so the remaining $80,000 tax debt can be paid off.

Similarly, in Loudoun County's District 32, challenger C. B. "Kelly" Burk (D), a schoolteacher and former legislative assistant to Sen. Charles Waddell, is well qualified to replace incumbent Del. Richard Black (R). Mrs. Burk is a bright and sensible progressive, in contrast to Del. Black's positions on guns, abortion and other issues.

On the other hand, energetic challenger Eileen R. Filler-Corn (D) has not presented sufficient reason to unseat incumbent Del. James H. Dillard II in District 41. Del. Dillard, a Republican, has a long record of effective leadership in the House, and as co-chairman of the Education Committee he remains well positioned to help Northern Virginia.

Other incumbents who deserve support include Republican Vincent F. Callahan in District 34 of Fairfax County, co-chair of the Appropriations Committee and an invaluable contributor; Republican Jeannemarie A. Devolites of District 35 in Vienna and surrounding territory; Democrat Kenneth R. Plum of District 36 in Reston and western Fairfax; Vivian E. Watts (D), a transportation expert in District 39; Gladys B. Keating (D) in District 43; Alexandria's Marian A. Van Landingham (D) in District 45; Arlington's James F. Almand (D) and Robert H. Brink (D) in the 47th and 48th; and James M. Scott (D) in Fairfax County's District 53.

The voters of District 38 are lucky to have two well-qualified candidates. Del. Robert D. Hull, a Democrat, has ably represented this piece of inner Fairfax County and Falls Church. His work for gun control and on behalf of the region has earned voter support. Challenger Stephen F. Smith, a lawyer and former Supreme Court clerk, is the kind of thoughtful, moderate Republican who could do great good in Richmond. The district will be well served in either case.

Finally, two well-qualified candidates are vying for an open seat in District 44, which Toddy Puller has represented. Scott T. Klein is an energetic Republican with solid ties to the business community. But Kristen J. Amundson (D), with her experience as school board president and other community work, is the better choice.