Meanwhile, coming Texas primary may reveal a new political landscape

In characteristic grand style, Texas is about to hold the second state primary in the 1982 election season.

Big bucks, big boasts, big risks will be on the line this Saturday, May 1. Texans take to their politics with the same ebullience as they do their ranching and oil investments.

Indeed, the state's rapid economic growth the past two decades has had a profound impact on its politics.

Particularly on the Republican side, the entrepreneurial spirit that has made Texas a world energy capital and the Southwest's financial center has been matched by a spirit of political expansionism and hard-nosed investment in modern campaigning techniques.

The Republicans have set the pace, behind Gov. William Clements.

''This used to be a one-party state,'' observes V. Lance Tarrance, a Republican pollster based in Houston. ''In the 1970s it was called a party-and-a-half state. In the 1980s, if Governor Clements is reelected, it will be a two-party state.'' The Texas GOP trend has broad national political implications. Texas, a swing state in presidential elections, would help anchor the Southwest in GOP hands.

But the Texas GOP's strides are far from assured. Governor Clements faces a tough November fight from any of the three major Democratic contenders.

Democrats are expected to keep all 19 US congressional seats they now hold and Republicans the five they hold. The parties will likely each get one of the three new seats granted Texas by redistricting, with the third seat up for grabs. Democratic Sen. Lloyd M. Bentsen is favored to keep his Senate seat. In the state Legislature, Democrats should pick up seats as a result of redistricting.

Governor Clements, a plain-talking (some say abrasive) self-made millionaire, is counted on to drive the GOP's breakthrough political wedge in '82 and keep the state in position to help Reagan if he runs in '84.

''So much of the momentum of the Texas party is dependent on him (Clements), '' says Wayne Thorburn, executive director of the Republican Party of Texas. ''The other state GOP candidates' fate will depend on how well Clements does at the top of the ticket.''

Texas Republicans say Clements is a more crucial figure in politics here at the moment than is President Reagan - though the national economy has begun to strain the patience of even some well-to-do Texans.

''As one Houston businessman puts it,'' recounts pollster Tarrance, '' 'Houston may be recession-proof, but it sure ain't high interest rate-proof.' '' If interest rates don't come down, Reagan's standing will suffer even in Texas, Tarrance says.

So far, Texans have stood by Reagan. In the 1980 election Reagan carried Texas 55 percent to 41 percent for Jimmy Carter. Although Reagan's job approval has averaged close to 50 percent nationwide recently, and 55 percent across the South as a whole, it was about 58 percent in Texas, Tarrance says.

The President's appeal has been holding up well among independent-minded conservatives, anti-big-government Republicans, and urban business people, he says. But the potential remains for a big erosion in Reagan's Texas support if the economic recovery lingers, he adds.

Clement's Democratic rivals for the governorship say they will make an issue of his support for Reaganomics. But more of their focus will be on his style of governing and state issues like education.

The Democratic contenders in the May 1 primary include state Attorney General Mark White, railroad commissioner Arthur E. (Buddy) Temple, and land commissioner Bob Armstrong.

''Armstrong's been outgunned by money,'' concedes an Armstrong campaign aide. ''He's been trying to make that an issue, saying Mark White has special-interest money and Buddy Temple his family's money. White has a lot of support from conservative Democrats. He's the kind of governor that was nominated in the past. But he will have trouble getting the Hispanic and black votes he needs.''