Rep. Charles Thone (R-Neb.) took the first step in his effort to help the GOP reclaim the Nebraska governorship Tuesday when he won a five-man Republican primary.

Thone, a former state party chairman, gave up a safe House seat he has held for four terms in order to bid for the governorship Republicans have won only once since 1960.

He gained 45 percent of the vote to outdistance runnerup Robert Phares, former mayor of North Platte.

Thone will face Lt. Gov. Gerald Whelan (D), who had only nominal opposition for the Democratic nomination to succeed popular Gov. J.James Exon (D).

Exon, one of the architects of the surprising Democratic upsurge in traditionallly Republican Nebraska, is his party's unopposed nominee for the seat of rtiring Sen. Carl T. Curtis (R).

Curtis' longtime administrative assistant, Don Shasteen, had only a minor challenge for the dubious honor of opposing Exon in November.

In a mild upset, moderate Republican state Sen. Douglas Bereuter defeated conservative state Sen. Loran Schmidt (R) for the nomination to succeed Thone in the House. Former Democratic Party chairman Hess Dyas, who tried unsuccessfully for his party's Senate nomination in 1976, is Bereuter's opponent in what should be an interesting general election contest.

Two other House incumbents, Reps. Virginia Smith (R) and John Cavanaugh (D), were renominated and are favored in November.

Meantime, in West Virginia, the stage was set for the best Senate fight in years, when Sen. Jennings Randolph (D) and former governor Arch A. Moore (R) Brushed off minor challenges in Tuesday's primary.

Randolph, who came to Congress in 1932, and Moore, the state's best Republican vote-getter of modern times, both said they expect a close race in November.

In the only real primary contest in West Virgini, freshman Rep. Nick Joe Rahall (D) turned back the comeback bid of former Rep. Ken Hechler (D), who held the seat for 18 years prior to 1976.

Hechler tried unsuccessfully for governor in that year's Democratic primary and then mounted a write-in campaign against Rahall in November.

As was the case in 1976, Rahall heavily outspend Hechler. He has no Republican opposition in the general election. Three other West Virginia Democrats were renominated to the House and are favored in the fall.

Following are lists of winning congressional candidates in the West Virginia and Nebraska primary elections. Incumbents are indicated with an (I); candidates without opposition are indicated with an X. West Virginia

1st District

X - Democrat: Robert H. Mollohan (I), Fairmont.

X - Republican: Gene Haynes, Parkersburg.

2nd District

Democrat: Harlye O. Staggers (I). Keyser.

X - Republican: Cleveland K. Benedict, Lewisburg.

3rd District

X - Democrat: John SIck (I), Charleston.

X - Republican David M. (Mick) Staton, South Charleston.

4th District

Democrat: Nick J. Rahall (I), Beckley.

Republican: No candidate.

U.S. Senate.

Democrat: Jennings Randolph (I). Elkins, Republican Arch A. Moore, Glen Dale. Nebraska

1st District

Democrat: Heas Dyas, Lincoln.

Republican: Douglas Bereuter, Utica.

2nd District

Democrat: John Cavanaugh (I). Omaha.

Republican: Hal Daub, Omaha.

3rd District

X - Democrat: Marilyn Fowler, Lexington.

X - Republican: Virginia Smith (I). Chapell.

U.S. Senate

X - Democrat: Gov. J.J. Exon Lincoln.

Republicanm: Don Shasteen, Omaha.

Governor

Democrat: Lt. Gov. Gerald Whelan. Hastings.

Republican: Rep. Charles Thone, Hartington.