Correction: An earlier version of this story misstated the total number of people who voted in a similar 2012 special election, in which Libby Garvey won by 813 votes. State records show that 14,287 people voted in that race, not 90,449. This version has been corrected.

John Vihstadt, the independent candidate in the April 8 special election for the Arlington County Board, chats with local resident Linda Staheli, right, on March 8. (Amanda Voisard/The Washington Post)

Residents of overwhelmingly Democratic Arlington County will vote Tuesday in a County Board special election that observers are calling the most competitive in a decade.

Alan Howze, a Democrat, is facing John Vihstadt, a Republican who is running as an independent “fusion candidate” in an effort to become the first non-Democrat elected to the County Board since 1999.

According to campaign finance reports released this week, Vihstadt and Howze raised almost equal amounts of money in the past three months, an unusual development in the famously progressive county.

Howze raised $84,984 in the first quarter of 2014, and Vihstadt took in $84,154, according to results compiled by the Virginia Public Access Project.

“This has the feeling of a hotly contested County Board race of the kind that we haven’t had for years,” said Carrie Johnson, a longtime Democratic Party activist who closely follows local politics.

Throughout the campaign, Howze has raised $109,016, spending all but $5,170 of it. Vihstadt has raised $95,501 overall and has $20,379 left.

Although turnout is expected to be around 20 percent, the election — to fill a vacancy created by the resignation of longtime board member Chris Zimmerman — could indicate whether voters believe that the county government is on the right track or whether more fiscal accountability is needed.

At least 80 people came to a final candidates’ forum Thursday night at the Arlington Mill Community Center, to hear Howze, Vihstadt and two lesser-known candidates, Janet Murphy and Stephen Holbrook, answer questions that ran the gamut from the Columbia Pike streetcar to backyard chickens to whether bicyclists should have the right of way over pedestrians and cars.

Vihstadt is trying to tap into a strain of dissatisfaction about county spending on projects that include the streetcar and concern that the five-member County Board, which often votes unanimously, has become too insular.

Howze, who increasingly has expressed a willingness to examine spending priorities more closely, for the most part supports the decisions and priorities of the current board majority. In the last week of the campaign, he pushed Vihstadt to support the expansion of Medicaid in Virginia, which Republicans in the state legislature have resisted.

“I’m running for County Board — a local race — and focusing on local issues over which the County Board has jurisdiction,” Vihstadt said Thursday in an e-mail. “Medicaid is not one of those issues. That said, all Arlingtonians deserve affordable, accessible health care. I hope the Governor and General Assembly can work out their differences and do it soon.”

Howze and Vihstadt agree on a variety of issues, including the need to continue Arlington’s substantial investment in creating new affordable housing in partnership with nonprofit groups. Both rank their commitment to schools as among their highest values, and both say they want to encourage businesses to stay or move to the county, particularly given a commercial vacancy rate that’s reaching 20 percent in some areas.

Howze pushes back, however, against Vihstadt’s belief that a bus rapid-transit line is a better choice for Arlington than a new streetcar.

“We have benefited from those investments 50 years ago,” Howze said at the forum last night, a reference to the decision to bring mass transit to Arlington in the form of the Metrorail system. “To now say it’s just good enough to take the bus . . . shows a short-sightedness that is not in the long-term best interests of our community.”

Special elections are more risky for Democrats in the county than are those that occur during the regular cycle. The last two non-Democrats to serve on the County Board won their seats in special elections: Republican Mike Lane, in 1999, and Ben Winslow, a Republican who ran as an independent, in 1993. Two years ago, when Democrat Libby Garvey beat two challengers in a special election, she won by just 814 votes out of 14,287 cast.

In addition to the streetcar and overall spending, key issues for voters in this matchup include stop signs, potholes, school crowding and whether the Long Bridge Park aquatics center, now on hold, should go forward.

The powerful Arlington County Civic Federation, a meta-group of neighborhood groups, called this week for a reduction in the county’s tax rate, one of the first big issues that the winner of this election will help decide.

Most of the local Democratic establishment is backing Howze in Tuesday’s contest. But Vihstadt, endorsed by the local Republicans and Greens, is also backed by three well-known Democrats: Garvey, Commonwealth’s Attorney Theo Stamos and Peter Rousselot, the former chairman of the local Democrats and now a leader of the anti-streetcar group Arlingtonians for Sensible Transit.

An analysis by the Virginia Public Access Project shows that Vihstadt received more than $9,000 in donations from people who gave to Garvey and other Democrats in 2012, in addition to the support he received from donors to Republican candidates and causes.

The winner of the special election will complete Zimmerman’s term, which ends Jan. 1, and have the advantage of incumbency in running for a full term this fall.

Absentee voting is offered at the county building at 2100 Clarendon Blvd., Suite 320, until 5 p.m. Saturday.