In a state that has not voted Democratic in a presidential election since 1964 and has twice given over two-thirds of its votes to Ronald Reagan, the election of a Republican Senate candidate in Nevada this year would appear to be a safe bet. Especially since that candidate was personally picked and groomed by the popular Paul Laxalt.

But don't bet the farm on it: Nevada Democrats, unusually united behind the Senate candidacy of Rep. Harry Reid, may have discovered a theme that could work against the GOP in the West.

The principal reason for unity among Silver State Democrats is the Republican nominee, former Democratic congressman Jim Santini, whose 1982 Democratic primary challenge to longtime senator Howard Cannon is blamed by Democrats for Republican Chic Hecht's upset victory that November. Santini switched to the GOP last summer after Laxalt announced he would not be a candidate for reelection.

In an interview, former Democratic governor Mike O'Callaghan, still enormously popular in all the polls, said, "Jim Santini is a climber" whose "selfishness" cost the Democrats a Nevada Senate seat. Santini's announcement that he would be a candidate was marred by press questions about the Federal Election Commission's investigation of missing checks from the candidate's last campaign. It was followed by prominent Democrats' charges that he was a "turncoat," an "opportunist" who had been imposed on Nevada by the "national Republican establishment in Washington."

That last line could work for Democrats in Nevada this year. Like much of the West, Nevada has long had a love-hate relationship with the U.S. government. Sure, the neon signs in Las Vegas are lighted by electricity the feds provide. And, yes, the glf courses are green and the taps are full because of federal water projects. And federal payrolls have brought prosperity to the state.

But the federal government owns 87 percent of the state's land, and it's American to hate your landlord. Nevada voters have long preferred their senators and congressmen to be country slickers who, while paying lip-service to the cowboy capitalism the region trumpets, would regularly loot the federal Treasury for the state.

So it is possible that Harry Reid can effectively campaign against the federal establishment. Given the popularity of Reagan and Laxalt, such a strategy could be tricky. But remember: this is Nevada, a state whose economics -- founded on legalized gambling, federal payments and quickie divorces -- is in open conflict with its politics, which has become increasingly socially conservative and even moral majoritarian. Both Senate candidates oppose the Equal Rights Amendment in the same state where, in 15 of its 17 counties, prostitution is legal. But in the candid assessment of Republican adman and Santini adviser Sig Rogich of Las Vegas, "Morality takes a back seat to poverty."

The 1986 Senate race is without an overriding issue. The outcome, which could determine whether the GOP keeps its Senate majority, could hang on whether Nevadans think Republicans have finally become the Washington establishment.