Jeremy Fretts finishes voting at Fire Department Headquarters during a special election for a Virginia state delegate for District 45. (Matt McClain/FOR THE WASHINGTON POST)

Democrat Rob Krupicka decisively wona low-turnout, three-candidate special election Tuesday to fill the unexpired term of former state delegate David L. Englin.

Krupicka, a nine-year Alexandria City Council member who also serves on the state Board of Education, got more than 75 percent of the vote. Republican Tim McGhee had more than 20 percent, and Libertarian Justin Malkin garnered less than 4 percent.

Only 15 percent of the 55,000 active voters went to the polls Tuesday, which for many residents was also the first day of school and a return to normal work schedules after the Labor Day weekend.

“The margin is much larger than I would have expected,” Krupicka said moments after McGhee called him to concede. “This is a community I’ve worked with for a very long time. . . . We have important and serious issues to work on, and I’m really honored to be given this chance.”

The seat came open when Englin (D-Alexandria) announced this spring that he would resign in the wake of an extramarital affair. A little more than a year is left in the term.

John Meyering votes at Fire Department Headquarters during the special election for a Virginia state delegate for District 45. (Matt McClain/FOR THE WASHINGTON POST)

Gov. Robert F. McDonnell (R) set the special election date for both the Alexandria race and for a Norfolk area state Senate contest in which Del. Kenneth Cooper Alexander (D) is running unopposed for the seat of the late Sen. Yvonne B. Miller (D).

Krupicka raised $82,390 — far more than Malkin ($9,670) and McGhee ($5,745) combined, according to the Virginia Public Access Project. An additional $5,000 in last-minute donations came into Krupicka’s coffers from the state Democratic Party, the Virginia Education Association and Dominion Virginia Power. Much of his money was spent before the Aug. 4 Democratic primary, in which he beat Karen Gautney.

Tuesday’s victory was a comeback of sorts for Krupicka, who lost a Democratic primary last year for the state Senate seat won by Adam P. Ebbin (D). Ebbin beat McGhee in the general election.

District 45 is a traditionally Democratic area, making up eastern Alexandria, Arlington County’s Fairlington, Shirlington, Abingdon and Aurora Hills neighborhoods, and Fairfax County’s Belle View and Huntington areas.

Englin, while shutting down his Web site Friday, when his resignation became official, jumped the gun this past weekend and assumed a Krupicka victory.

“David Englin no longer represents Virginia’s 45th House of Delegates District,” the site said. “Your new state delegate is Rob Krupicka, who can be contacted at”

“That’s how confident I am in Rob’s victory,” Englin said Tuesday afternoon while polls were still open. “Sure, it’s a bit premature.”

Krupicka, 41, a self-described progressive who worked in technology and now is at an education nonprofit group, held off a challenge by McGhee, 35, a conservative web design business owner, and Malkin, 41, a credit analyst who was seeking office for the first time.

In local politics, Krupicka voted to expand mass transit, for environmental initiatives and to increase open space. This year, in the two most controversial decisions facing Alexandria, he voted with the majority to endorse the city’s plan to redevelop the waterfront and to allow the redevelopment of the Beauregard area in the West End.