The Republican Party, all but pronounced dead a few years ago, is gradually accepting the once preposterous-sounding notion that it can overtake the Democrats as the nation's majority political party during the 1980s.

That was the clear message to emerge from the semiannual meeting of the Republican Natinal Committee that ended yesterday. It was perhaps the most euphoric RNC gathering in a decade.

"The mood is very upbeat, very optimistic," said Iowa national committee member Mary Louise Smith, a veteran of such sessions. "you would have to go back to the early Nixon years to find anything like it."

"There's a general feeling that 1980 wa a watershed year, and we're on top," said Kentucky national committeeman Larry Forgy.

Although expected complaints about patronage and failure of the Reagan administraton to appoint more women to jobs surfaced, there was virtually no controversy during three days of meetings.

The only hint of conflict came over National Chairman Richard Richards' opposition to independent conservative political action groups, such as the National Conservative Political Action Committee, which conduct campaigns to defeat Democrats. He has said such groups "create mischief."

But there was little support for sanctions against such groups. State chairmen and the party's rules committee, in separate sessions, refused to consider a resolution about them. And a poll by Cbs News found RNC members, by a ratio of 2 to 1, think these groups strengthen, rather than hurt, the party.

In one of the few formal actions during the three days, the national committee created a panel to study election reforms, including the role of independent expenditure groups, many of them on the far right. But there were indications that Ernest Angelo, a conservative Texan named to head the reform committee, doesn't share Richards' views.

"I think independent expenditure groups have a role to play in view of the restrictions on individual contributions," Angelo said. He adknowledged there "have been some instances when independent expenditure groups have caused problems," but he added "we need to be very careful on legislating what people can do."

By all indications, the Republican Party is fat, comfortable and confident. Two-thirds of the RNC members polled by CBS News predicted the party will take control of the House of Representatives in 1982; four of five expect Reagan to run for reelection; 99 percent approve of his budget cuts, and 97 percent like his tax cut proposals.

If Reagan doesn't run, 41 percent would like to see Vice President Bush be the party nominee; Rep. Jack Kemp (R-N.Y.) was a distant second with 8 percent. A cloud of suspicion still hangs over Richard Nixon; only one RNC member in five would like him to campaign in their state.

Although almost two-thirds of the committee members consider themselves conservatives, a clear majority came down on the liberal side of the abortion issue, saying that if a woman wants to have an abortion and her doctor agrees to it, she should be allowed to have one.

The GOP will go into 1982 with a healthy war chest. It already had $9.3 million in the bank, and finance chairman Richard Devos, co-founder of Amway Corp., announced plans to raise $29 million, at a cost of $8 million, this year. This would leave $21 million, a record budget for a non-presidential year.

The party is also attracting more candidates than any time in recent years. Nancy Sinnott, executive director of the National Republican Congressional Committee, said there are already 150 GOP candidates for Congress, three times as many as at the same point two years ago. Her committee will start workshops for 1982 candidates next month; previously they didn't start before February of election year.

"We're ready and we're anxious," Sinnott said.