In Mathews County, the voter registration office was in the back of a furniture store, poorly marked and open only two days a week. In Brunswick County, it took the resignation of the local registrar before the county would set up satellite registration sites to sign up rural residents to vote.

These were some of the roadblocks encountered this summer during a statewide voter registration drive by Virginia Action, a newly formed activist coalition. They are also examples of why Virginia--with 53.7 percent of its voting age population registered in 1982--ranks among the bottom three states in the nation in voter registration.

This year, at the urging of veterans of last summer's battles, Sen. L. Douglas Wilder (D-Richmond) and other black legislators introduced a series of bills to force Virginia's local election officials to change their ways.

And in Virginia, where for two decades the Byrd organization kept voter participation at an average of 11.5 percent of the adult population, change has been a long time coming. For blacks in rural areas, the unwillingness to encourage registration is a painful reminder of their virtual disenfranchisement during the days of the poll tax and literacy requirements.

This year's package of voter registration reforms, introduced in both House and Senate, already has been dealt setbacks by the conservative members of both the House and Senate Privileges and Elections Committees.

The first measure to die would have eliminated Virginia's constitutional requirement that residents register to vote in person. Until that provision is removed, registration by mail--now allowed in 21 states--is impossible in Virginia.

Killed in both houses were bills requiring local registrars, relying on unpaid volunteer deputies, to set up satellite registration sites around the county upon the request of at least 10 residents. Also dead are bills that would have moved the deadline for registration up to 21 days, rather than 31 days, before an election.

On a major bill to force registrars to cooperate with voter registration drives, the Senate committee toned down language--stricken outright in the House--that specifically allowed volunteer registrars to "actively solicit" voters at shopping centers, swimming pools and other public places.

One of the few reforms likely to survive both the House and Senate is a measure requiring local registrars to list the office's telephone number in local phone books. Even that was debated at some length in the House committee, as delegates wanted to know where exactly in the phone book the registrar's listing should go.

Yet the survival of even a handful of voter registration bills this year was hailed as a victory in the campaign to widen Virginia's electorate. "What we have gotten is clearly a step forward," said Fritz Wiecking, executive director of Virginia Action.

In the Senate Privileges and Elections Committee, where the voting package was taken up hurriedly in the crush of a legislative deadline, an impatient Senate Majority Leader Hunter B. Andrews (D-Hampton) cautioned Wilder and other lobbyists. "You've gotten right much here today," said Andrews. "Don't go too far."

Afterward, Wilder said he was particularly happy about the bill requiring registrars to cooperate with registration drives. "If I can get that through the Senate, that's the nut in the coconut," said Wilder.

But like others, Wilder is waiting for next year when he is counting on Gov. Charles S. Robb to throw the weight of the administration behind voting reforms. Last year, Robb had proposed registration through the state Division of Motor Vehicles, but that idea has since been held up for study.

Problems faced by voters in parts of Virginia were documented in a recent study published by the organizers of last summer's drive. Although organizers found the greatest resistance in rural areas, some of Virginia's cities and urban counties show low registration rates. For instance, while Fairfax County registered 67.9 percent of eligible voters in 1980 (close to Maryland's 68 percent), Arlington was lower, with only 61.4 percent, as was Alexandria, with 56.2 percent.

The study showed a widely disparate response to the registration drive around the state. In some counties, local registrars accepted help from volunteers and set up registration sites in every precinct. But in other areas, the response was at best, resistant and at worst, hostile, officials said.

Halifax County, for instance, has only one voter registration office, 50 miles away from some parts of the county. Only after appeals were made to the U.S. Justice Department and the state Board of Elections did the registrar finally--in late September--agree to set up registration sites in black-majority parts of the Southside county.

In the city of Waynesboro, the registrar told organizers she wouldn't set up a temprorary site at one local shopping center because she would be discriminating against other shopping centers in the region.

Robb, in his first year in office, said broadening Virginia's electorate would be a priority of his administration. But this year, Robb kept aloof from the legislative initiatives, arguing that there was not enough time in the General Assembly's so-called "short session" to tackle the problem.

Sue Fitz-Hugh, the newly named secretary to the state Board of Elections, said last week she wanted to reserve judgment on some of the reform proposals.

"I'm for increasing voter registration in Virginia," she said. "But it is hard to pinpoint in this short time whether some of these bills are going in the right direction."

She noted, for instance, that a bill killed in committee, requiring registration days in local high schools, might have allowed rural registrars to close their regular offices to go into the schools.

These and other proposals will be studied later this year in preparation for a full package to be introduced by the administration in 1984, said Fitz-Hugh. "We're getting half of it this year," she said. "Maybe next year, we will get the other half."