A political and legal tussle is gaining force in Northern Virginia over guaranteeing a fair vote on Election Day. Fairfax County Democrats are complaining that Republican-appointed county elections officials are breaking or twisting some rules to help the GOP in the biggest jurisdiction in a key swing state.

The arguments might end up in court in the next two weeks. The disputes are mainly over Republicans’ plans to restrict activities by party lawyers and other elections observers inside polling places and to limit access to provisional ballots while a decision is made on whether to count them.

The GOP says that federal and state law support its policies. Democrats say that the Republicans are violating or misinterpreting the law, with the possible result that legitimate votes will go uncounted.

“At some point, we must consider litigation. We would be reckless if we don’t make some of these concerns known,” said Cesar del Aguila, chairman of the Fairfax County Democratic Committee, who raised some of the concerns in writing as far back as January.

Democrats also worry that the process could be tainted because some top officials in the Republican-controlled county election apparatus have records as aggressive GOP partisans.

In particular, Hans von Spakovsky, who is vice chairman of the Fairfax Electoral Board, is one of the nation’s most prominent advocates of voter identification laws strongly opposed by Democrats.

Von Spakovsky, a senior legal fellow at the conservative Heritage Foundation, is one of two Republican appointees on the three-person board. The GOP controls electoral boards in the state right now because Gov. Bob McDonnell is a Republican.

Von Spakovsky’s work on voting issues in the Justice Department in the George W. Bush administration was sufficiently controversial that congressional Democrats blocked him from being appointed to the Federal Election Commission in 2008. He thinks Virginia’s new voter ID law is too lenient.

“I’ve read about his background. I’m concerned why and how he ended up in Fairfax County in his role,” del Aguila said.

Von Spakovsky said the GOP recruited him for the part-time Fairfax job because of his expertise gained in a quarter-century of work in election law.

“Take every single Democrat you’ve spoken to, and I bet I have more experience in election law and election administration than all of them combined,” he said.

It’s hard to overstate the potential stakes. Virginia, along with Ohio and Florida, is one of the principal battleground states whose electoral votes are being hotly contested in the presidential race.

Moreover, blue-leaning Fairfax is both Virginia’s most populous county and by far its largest source of potential Democratic votes.

If the national election is close and the vote in Virginia is disputed, then Fairfax and its election procedures could conceivably become a focus of national attention, much as Florida was during the 2000 recount.

The controversy highlights the generally overlooked reality in America that the people given the job of protecting the neutrality of the election process are often far from neutral themselves.

“It’s problematic that we have elections administered by partisan election officials, which is not how most mature democracies run their elections,” said Richard L. Hasen, a professor at the University of California-Irvine law school who specializes in election law.

“It’s not just about their potential for actual bias. It’s also the potential subconscious bias. On top of that is the problem of public perception,” Hasen said.

In addition to their worries about von Spakovsky, the Democrats are expressing concern that a longtime Republican activist, Cameron Quinn, is the county’s general registrar. That means she runs the county elections office, with a staff of 27, under the guidance of the electoral board.

Quinn said the Democrats’ complaints “saddened and disappointed” her and that she proved she could be objective when she served as secretary of the State Board of Elections from 1999 to 2003.

“I park my partisanship at the door when I walk in,” Quinn said.

The Fairfax Democrats’ general counsel, John W. Farrell, sees it differently. He accused Quinn of helping to change rules to prevent the party’s elections observers — often lawyers — from walking around inside polling places and from speaking to voters to make sure they know their rights.

Among other things, Farrell wants the observers to be able to advise voters who lack proper identification that they can go home and retrieve it. Within 40 feet of the polling place, the observers would not be allowed to advise people how to vote.

Farrell said Quinn was trying to rein in the Democrats’ poll-watching operation in Fairfax because Republicans supposedly didn’t have enough people to staff all 237 precincts in the county.

“Rather than generate their own program, she tries to castrate our program,” Farrell said.

Quinn said she’s just following state guidelines.

Farrell also said the Democrats wanted to be able to see the name and address of every person who votes a provisional ballot — partly to avoid tampering.

“We want to make sure all of these voters are real, living people,” he said.

Von Spakovsky said federal law prevents such access.

“If they think that’s a problem, then they should file suit. And they’ll lose, because federal law is crystal clear,” he said.

It’s all awfully reminiscent of that 2000 Florida recount — where, incidentally, von Spakovsky was an observer for the Bush campaign.

For previous Robert McCartney columns, go to washingtonpost.com/