The Maryland Republican Party yesterday overwhelmingly voted to delay deciding whether party nominees should be endorsed at a convention before a primary.

The vote came after a lengthy and bitter day of debate at the party's annual central committee meeting. It effectively dashed any hope GOP leaders had of holding a convention before next year's 1982 gubernatorial election. Instead, party leaders may again consider the motion in spring 1983.

Under the proposed changes, the GOP would have endorsed a slate of candidates for governor and three state offices several months before the primary.

Although an endorsed candidate would still have to run in the primary under Maryland state law, proponents had hoped that approval of the measure would give slate candidates an early start in this heavily Democratic state where Republicans have won only four state offices in the last 20 years. Registered Democrats outnumber Republicans 3 to 1 in Maryland.

The overwhelming decision to delay the measure was seen by some GOP committee members as a vote of confidence in Prince George's County Executive Larry Hogan's bid for the U.S. Senate in 1982. The push for the 1982 convention had been seen by some in the party as a move to temper support for Hogan, who expects to receive more support from voters in an open primary than from party regulars at a convention.

"I think it was the right thing to do," Hogan said moments after the vote in the conference room of the Washingtonian Motel in Gaithersburg. "Philosophically I am opposed to it. It seems counter to the open-door policy the Republican Party has always had. And it would put the selection process into the hands of a smaller group of people."

Proponents of the measure disagreed with Hogan, arguing that the excitement of a convention would pull more voters into the party and encourage local workers to get involved in campaigning. Under the proposal, as many as 2,500 delegates could have been elected to the convention.

"It really gives us a chance to organize at the grass-roots level," said Linda Love, a member of the Anne Arundel Central Committee, who warned that defeat of the motion or even temporary delay could effectively kill Republican chances of gaining any state offices in the coming election.

"I really think we're throwing the baby out with the water . . . . It takes more than a great candidate to win . . . . You need to get the money, get it spent and get that Republican elected. You can't do that in five weeks."

In Maryland, state primaries are usually held about two months before the general election. That short period, Republicans like Love argued, made Democratic incumbents almost impossible to beat.

Some committee members said they opposed the proposal because it was flawed. Opponents questioned whether the party could elect 2,500 delegates in time for a spring convention and whether once a candidate was selected, he would win the primary.

"I'm concerned that if candidate A is endorsed and the voters elect candidate B what that will look like for the party," said Carroll County Chairman Glenn Speicher. "The fact that we will have a convention means nothing. It's all cosmetic."

State party chairman Allan C. Levey, who initially conceived the idea for the convention last spring, said the convention would rally the kind of support for a slate of candidates that developed in the Virginia conventions earlier this year. They were the first held in the state in 16 years, and replaced the primaries.

"When you're talking about a convention you're talking about walking away with a thousand volunteers," Levey said. Virginia Democrats won all three state offices this year.