An unpublicized meeting last weekend in the Great Smoky Mountains of Tennessee may turn out to be an important landmark in the ongoing saga of the Republican Party's effort to become the governing party in America.

Four leading governors, three conservative House activists and two of the Republicans' most influential political consultants met at Blackberry Farms for the off-the-record session.

The host for the meeting and its prime mover was Tennessee Gov. Lamar Alexander, who will take over this summer as chairman of the National Governors Association. The other governors were Dick Thornburgh of Pennsylvania and John Sununu of New Hampshire, chairman and vice chairman of the Republican Governors Association, and Jim Martin of North Carolina, a former House member. With them were pollster Robpaign consultant Douglas Bailey, products of the party's progressive wing and strategists for many GOP gubernatorial candidates.

Joining them were three of the leaders of the House Conservative Opportunity Society, the often controversial group that thinks of itself as the cutting edge of "the Reagan Revolution": Reps. Newt Gingrich of Georgia, Connie Mack of Florida and Carroll Campbell of South Carolina.

The session was the result of a call from Alexander to House Minority Whip Trent Lott (R-Miss.), in which the governor, as he told me, "expressed my frustration" that whenever the GOP had a campaign strategy meeting, "we get a wagonload of Washington, D.C., operatives talking about the gold standard and Afghanistan and a lot of other things that can't possibly get a Republican elected mayor of Johnson City.

"I told Trent that some of his right- wing friends have helped the president find a way to talk about issues that boosted the Republicans on the national level, but we don't seem to do that well at the state or local level. I asked him if he could get some of us together with some of his friends and see if we couldn't come up with some ideas." The upshot was the Blackberry Farms meeting, which Lott himself missed because of a schedule conflict. All the participants I interviewed said it was probably the best brainstorming and strategy session they had ever attended.

Out of it came the outlines of what the participants found themselves calling "Reagan Revolution Stage 2," an effort, as Thornburgh put it, "to extend GOP victories beyond the Beltway" in the 1986 elections.

It is not idle talk. Thornburgh and Sununu already are well launched on a campaign to raise $2 million for the Republican Governors Association to use in the 38 gubernatorial elections of 1986. They have signed up President Reagan for an autumn fund-raiser that will give the feeble RGA its first real financial and political credibility.

The Blackberry Farms meeting is the start of a parallel effort to give it intellectual substance by identifying GOP themes and programs that rely on state level leadership. In addition to the obvious one of education, the group spontaneously focused on the need to improve America's competitiveness in the international economy -- including what Gingrich called "mutual trade" policies as an alternative to free trade or protectionism. These ideas will be fleshed out at later sessions.

Even at this early stage, there are three important lessons to be drawn.

The spontaneous focus on job development and trade policy -- which the Reagan administration has brushed aside with laissez-faire nostrums -- shows the usefulness of a party's mixing state and federal perspectives. It carries a warning to the Democrats -- who have just launched a national policy commission dominated by state and local officials but with a cumbersome 100 people involved -- that these nine smart and fast-moving Republicans are out to steal their lunch.

Second, it sends a message to establishment Republicans in Washington, who dismiss Gingrich and his gang as publicity-seeking bomb-throwers. Alexander, a close ally of former Senate majority leader Howard H. Baker Jr., and Thornburgh, Sununu and Martin -- the mainstream of the GOP governors -- are certainly not crazies. They went to Gingrich & Co. not for advice on kamikaze tactics but for ideas -- and found them there. House Republican moderates, who have talked about meeting with their party's governors but typically procrastinated, have once again been bypassed.

Finally, these Republicans have the germ of an idea that could in fact move the Reagan Revolution into a new phase. Campbell, who will leave the House next year to run for governor of South Carolina, put it best: "We have won at the national level by promising to restrain the federal government's role. But people want and expect their state governments to be active and involved in solving problems."

That is the message that was missing from Reagan's abortive 1982 federalism initiative and is still missing from the national GOP rhetoric. I am more convinced than ever that the 1986 gubernatorial elections are the next critical battleground for American politics, and the Democrats, who now control two- thirds of the states, had better understand that the Republicans are coming at them in a more serious way than they have ever seen.