If voter registration figures are an accurate indication, District residents are excited about next month's primary election for mayor and other city offices, while several primary contests in Maryland have left voters cold.

Yesterday was the last day Maryland and District residents could sign up to vote in Sept. 11 primary elections, and officials in the two jurisdictions say registration figures there tell contrasting stories about voter interest this election season.

Leona Agouridis, a spokeswoman for the D.C. Board of Elections, said that more than 40,000 new voters have been added to the city rolls this year, a record high for a non-presidential election year. Although final numbers were not available yesterday, she estimated that almost 300,000 voters will be eligible to cast ballots in next month's elections.

Agouridis attributed the high interest in part to the hotly disputed contest for the Democratic nomination for mayor and in part to vigorous efforts to increase voter registration. Last-minute registrations continued to pour in yesterday, including 500 submitted by Jesse L. Jackson's Rainbow Coalition. Jackson conducted a weekend registration sweep that included a trip to the Lorton Correctional Center, where he signed up 100 new voters.

In Maryland, by contrast, state and county officials say new voters are signing up at a slower pace than in previous gubernatorial election years. Although Gov. William Donald Schaefer has no opposition within the Democratic Party, there is a contest to determine the Republican gubernatorial nominee. In the Washington area, there are several primaries involving members of Congress and the General Assembly.

One of the most closely watched primaries pits Maryland Rep. Steny H. Hoyer against Abdul Alim Muhammad, the national spokesman for the Nation of Islam, for the Democratic nomination in Maryland's 5th Congressional District, which includes most of Prince George's County. Muhammad said several weeks ago that he hoped to register thousands of new voters in his bid to oust Hoyer.

Prince George's County election officials said yesterday that Muhammad's supporters turned in 1,000 registration cards this weekend and that they had previously registered several hundred others. Muhammad said yesterday that the registration campaign "didn't achieve our goals with regard to numbers," but that "overall, we're pleased with the effort.

"I'm sure that over the past six weeks we've registered several thousand voters," Muhammad said. "And we think we will be able to get apathetic voters out. We feel we would benefit from a high turnout."

A spokesman for Hoyer declined to comment yesterday.

Statewide, Maryland officials said that the total number of registered voters is lower than it was before last year's presidential election because thousands of people who had not voted since 1984 were purged from voter rolls earlier this year. State Elections Administrator Gene Raynor said that in the years after a presidential race, new registrations usually more than make up for the number of voters purged.

"It's very, very quiet, and that's not customary," Raynor said. "There's a lot of voter apathy out there."

As of June 30, the most recent numbers available, Maryland had about 2,070,000 registered voters. Immediately before last November's presidential election, the state had about 2,149,000 registered voters.

In the District, Agouridis said that aggressive registration efforts by the government and by independent groups have boosted registration. Since April of last year, the District's Motor Voter program has allowed people to register to vote at the same time they get their driver's licenses. And groups such as the Rainbow Coalition are conducting registration efforts of their own.

Jackson said yesterday that at his Friday visit to Lorton, he registered 100 inmates who had not been convicted of felonies and therefore had not lost their voting privileges. "It's their right," he said.

"We've been to hospitals, schools, churches" with registration efforts, Jackson said. But he said the District's registration deadline, which ended efforts to sign up new voters almost a month before the primary, "effectively disenfranchises thousands of people."

"Many people have not focused on the election," he said. "They will become stimulated about 10 days before the election. And they will not be able to vote."

In Maryland, officials in Prince George's and Howard counties said they have fewer voters on the rolls than they did Jan. 1, while in Montgomery County that number is about even.

Montgomery County registration supervisor Mary Moore said activity there has been "very, very light," while Prince George's County election supervisor Robert J. Antonetti said registration "has not been staggering."

In both the District and Maryland, Democrats continue to vastly outnumber Republicans. According to numbers available yesterday, District Democrats hold an advantage of more than 10 to 1 in registration, 229,000 to 26,000.

Maryland Democrats outnumber Republicans more than 2 to 1, but their numerical advantage has slipped slightly over the past two years. As of June 30, about 63 percent of registered voters were Democrats and 29 percent were Republicans. In November of 1988, 64 percent were registered as Democrats and 28 percent as Republicans.