It is spring, and everything is possible. So please do not laugh when I tell you that the moderate-progressive Republicans are plotting their comeback.

Yes, I know that sounds silly in the Age of Reagan, when conservatism is in the saddle -- especially in the Republican Party.

All I can tell you is that three quite sane and professional Republican members of the House sat down on a couch recently and told me how they and their friends hope to redirect the policy of their party in coming years.

They were Stewart B. McKinney of Connecticut, Olympia Snowe of Maine and Tom Tauke of Iowa, and they are three of the leaders of the "92 Group." The name was chosen to reflect their eagerness to be part of a Republican majority in the House by 1992 and their belief that such a majority cannot be achieved without broadening the philosophical range of the GOP beyond the confines of "the New Right."

There are 30 declared members of the group and another two dozen of what Tauke calls "closet members," who for a variety of political reasons do not want to affiliate formally.

They began meeting shortly after the 1984 election, spurred by a shared fear that Reagan's victory would be turned into a right-wing ideological triumph by the activist conservatives in the House. The shock troops of those forces are the members of the "Conservative Opportunity Society" (COS), led by Reps. Vin Weber of Minnesota and Newt Gingrich of Georgia.

In 1984, the COS adherents became the most vocal Republican debaters in the House. They put their stamp on the 1984 platform. They recruited and indoctrinated challengers for Democratic-held seats and generally acted, Snowe said, as if "they were the future of the Party."

While insisting they are not trying to "undermine" their conservative colleagues, McKinney said that "two-thirds of my constituents disagree with the planks on abortion and school prayer those people put into the platorm. . . . Those people may reflect their districts, but if we're ever going to win a majority we sure as hell have to have people like us running in districts like those we represent."

Snowe chimed in to claim that, "We have abandoned traditional Republican values in the field of arms control, environment and equal rights." And Tauke, going even farther, asserted that, "The majority of House Republicans would be more comfortable with a platform we would write than the one that was written in Dallas."

That remains to be tested, but the moderates are mobilizing around an issue that will gauge the future direction of the GOP as clearly as any: the budget. They are drafting a budget proposal of their own envisaging "across-the-board cuts" in both military and domestic spending, Tauke said, and have informed their party leadership that they will insist their views be considered before they are called upon to line up behind whatever the White House and the party leadership finally endorse.

It is a measure of the moderates' weakness that not one of their members has a seat on the budget committee. But Tauke is probably right in saying that "if we can pull 30 or 40 people together on the principles of our moderate budget, we can have an impact on the process."

That is particularly true, since House conservatives are divided among themselves on the spending issues. When I wrote recently about the running budget policy debate between Rep. Jack Kemp (R-N.Y.) and Rep. Bill Gradison (R-Ohio), COS leader Weber called to say that he and many other conservatives disagreed with Kemp's faith that economic growth could substantially solve the deficit problem, and were prepared to vote for spending cuts -- including the military.

But the ultimate test of the moderates' comeback efforts will be determined, not in the 1985 budget battle but in the 1988 convention fight.

They are not without allies. There is a significant cadre of moderate-progressive GOP senators -- including Majority Leader Robert Dole (R-Kan.) and the chairmen of such committees as budget, finance, appropriations, intelligence, foreign relations, commerce, environment and public works, and small business. There is a similar cadre of moderate-progressive governors in New Jersey, Pennsylvania, Illinois, Tennessee, North Carolina, Rhode Island and Delaware, and there will probably be more in 1986.

McKinney, a backer of Vice President George Bush, said: "Most of us will end up in the same camp in 1988." But how effective they will be depends on how much real political organizing they do off Capitol Hill between now and 1988.

Staff members from the "92 Group" offices have begun monthly meetings with the few, tiny progressive Republican organizations that exist, such as the Ripon Society. But the moderates simply do not have the political and financial infrastructure the conservatives have built over the past two decades.

As Tauke said, "For too many years, being a moderate in the Republican Party has been synonymous with being lackadaisical. We are learning from the conservatives that we have to be activists."

It is news -- and good news -- that the moderates are trying. But it is obvious they are starting late and have a long way to go.