THE RETIREMENT of a pair of veteran state senators in Northern Virginia, both Democrats who have served since 1996, has produced primary battles for the two soon-to-be-open seats. Both districts are Democratic-leaning, a posture that the party, which narrowly controls the state Senate, made sure to maintain in Virginia’s recently completed redistricting process. Primary voting has already started for absentees and culminates at the polls Aug. 23.

In the 30th Senate district, which includes south Arlington and parts of Alexandria and southeastern Fairfax County, three relatively well known and politically experienced politicians, all liberal Democrats, are in a race to replace Sen. Patricia S. Ticer.

The strongest of them are Adam P. Ebbin, a member of the House of Delegates, and K. Rob Krupicka, an Alexandria City Council member. Both Mr. Ebbin and Mr. Krupicka are well respected, substantive and effective, and either one would make an excellent senator. We’d give Mr. Krupicka a slight edge, based on his private-sector experience and expertise in education. The third candidate, Arlington School Board member Libby T. Garvey, is less ready for prime time in Richmond.

A member of Virginia’s state Board of Education, Mr. Krupicka has also worked on education issues in Alexandria and, until recently, at the Partnership for America’s Economic Success at the Pew Charitable Trusts. On the City Council, he’s won high marks from colleagues and constituents who regard him as quick-minded, conscientious and not overtly partisan, all qualities that would make him a player in Richmond.

The winner of the primary in the 30th will face Republican Tim McGhee, a businessman, in November.

The second major Democratic primary is in the 31st Senate district, which takes in much of Arlington and a strip of Fairfax County along the Potomac, including Great Falls and part of McLean, as well as the northeastern corner of Loudoun County. There, a political veteran is in a tough primary against a relative newcomer to replace Sen. Mary Margaret Whipple.

Although the newcomer, Jaime Areizaga-Soto, has a solid legal background in private practice as well as in the Army National Guard’s Judge Advocate General Corps, his track record of involvement with state issues is relatively recent and thin. The veteran, Arlington County Board member Barbara Favola, is clearly the stronger and more substantive choice, and would make a better senator.

Ms. Favola has served on the Arlington Board since 1997, including three one-year terms as chairman. She has also lobbied in Richmond on behalf of Marymount University, making her deeply conversant with the challenges facing higher education. She is steeped in Northern Virginia issues to the point of wonkishness; we mean that as a compliment, because a grasp of local affairs can translate into legislative savvy. While Mr. Areizaga-Soto’s campaign has stressed hot-button and partisan social issues, Ms. Favola stands a better chance of making headway on education, transportation and other areas critical to her constituents.

The winner of the Democratic primary in the 31st will face Republican Caren Merrick, a successful and well-funded high-tech entrepreneur, in November.

In addition to those State Senate contests, there is also an open-seat primary in what may be the most heavily Democratic district in the state: the 49th House of Delegates district, which comprises parts of southern Arlington and a slice of eastern Fairfax County. There, Alfonso H. Lopez, formerly the state’s top lobbyist in Washington, is a vastly more qualified candidate than Stephanie L. Clifford, who has some experience with national issues but little background at the state level.