Challenger Bill Gunter defeated Sen. Richard Stone in today's Democratic Senate runoff, while Paula Hawkins trounced Lou Frey Jr. for the Republican nomination.

With 67 percent of the 3,597 precincts reporting, Gunter had 54 percent to Stone's 46 percent. Hawkins had 59 percent to Frey's 41 percent.

Three other U.S. senators have been denied their party's nomination by voters this year -- Jacob Javits (R-N.Y.), who will be on the Liberal Party line in November; Mike Gravel (D-Alaska), and Donald Stewart (D-Ala.).

Stone, a 52-year-old first-term senator, had counted on a big vote in the urban areas of south Florida, his home base, in a replay of the 1974 Senate runoff he narrowly won. Gunter, the state's 46-year-old insurance commissioner, makes his home in Orlando and looked for strength from central Florida, the area he served in the House.

Both men emphasized get-out-the-vote techniques designed to deliver their voters to the polls.

It was the second Senate bid for Hawkins, 53, a member of the Republican National Committee who got committee aid for her campaign. She failed in a race for the party nomination in 1974.

Frey, 46, had hoped he could offset the advantage Hawkins gained from a strong showing in the Sept. 9 primary. But the campaign went slowly, and issues Frey raised seemed to attract little attention.

Florida voters also overwhelmingly approved a five-part package of constitutional amendments designed to give tax breaks to new and expanding businesses, and provide property tax relief to homeowners.

The only House runoff was in the 5th District, where attorney Bill McCollum defeated state Sen. Vince Fechtel for the GOP nomination after burying Abscam-tainted incumbent Richard Kelly in the September primary. McCullom meets Democrat David Best in November.

Stone's campaign was marked by an unusual announcement Monday by the Justice Department clearing the senator of any involvement in purchase of surplus peanut oil.

The Dallas Morning News said Sunday a federal grand jury was investigating whether Stone and other political figures were involved in the 1977 purchase of millions of pounds of government surplus peanut oil below open market prices by Frito-Lay Inc., a subsidiary of PepsiCo Inc. The newspaper did not cite any connections.

Stone topped Gunter by 20,000 votes in the primary, but admitted he faced an uphill struggle in the runoff. They bitterly criticized each other during the campaign, in a replay of their bitter battles of six years ago.