LITTLE ROCK, ARK., AUG. 18 -- Rep. Richard A. Gephardt (D-Mo.) took a backhanded swipe at Massachusetts Governor Michael S. Dukakis today as three Democratic presidential candidates presented their pro-defense views to southern legislators meeting here.

"We can't be against every weapons system and win the presidency," Gephardt said. "I don't know what he {Dukakis} is for. I now know what he is against," said Gephardt, whose votes for the MX missile and nerve gas production have been criticized by Dukakis. Dukakis is scheduled to appear here Wednesday.

Senate Minority Leader Robert J. Dole (R-Kan.), one of only two GOP presidential candidates to speak to the Southern Legislative Conference, denounced "crystal-ball liberals" who are "distorting" the record of Supreme Court nominee Robert H. Bork. He also sought to deflect conservative criticism of President Reagan's role in Nicaraguan peace proposals by pledging to press for additional military and humanitarian aid to the contras if there is no diplomatic progress by Sept. 30.

All three Democratic presidential candidates emphasized moderate to conservative stands to the estimated 1,100 elected officials at the conference, over three-quarters of whom are Democrats.

These legislators may prove important in the March 8 "Super Tuesday" primaries, when 14 southern and border states will pick delegates to the presidential nominating conventions in what will amount to the largest regional primary in the nation's history.

Sen. Albert Gore Jr. (D-Tenn.) contended that creation of Super Tuesday has reduced the ability of Democratic interest groups to establish a "set of litmus tests and narrow agendas to the exclusion of the attention that needs to be given broader issues."

Gore said he is prepared "to do whatever is necessary to protect our national security and to have a strong defense." And he declared his support of U.S. military backing to the shipping of oil in the Persian Gulf. "It would be a mistake to respond to the threats of Iran and abandon the principles of the freedom of the seas, and turn tail."

He expressed support of the rebels in Afghanistan but would not go that far in the case of Nicaragua. The people of Nicaragua, he said, "have not been offering support to the contras."

Former Arizona governor Bruce Babbitt told the legislators that the Democratic Party has to adopt "an agenda of economic growth" and to abandon its treatment of the federal government as a "giant check-writing machine, spewing out checks, redistributing income . . . . I didn't come here to make you a bunch of promises" about grant programs.

While Democratic presidential candidates attempted to redefine the party's ideology, the head of the Republican Party sought to capitalize on the turbulence within the opposition ranks.

Frank J. Fahrenkopf Jr., chairman of the Republican National Committee, came loaded for bear -- "the special interests of the far left are still the gatekeepers of the Democratic Party" -- but quickly ran into a hostile challenge from the floor.

In an unusually tough speech, Fahrenkopf warned the southern legislators that "the national Democatic Party is a liability to you, a fracture point between you and your constituents. How much longer can you support a party so much at odds with the beliefs, the values and the traditions of the South? . . . The people of the South are fed up with the national Democratic Party."

Immediately after Fahrenkopf finished, however, North Carolina state Sen. Ken Royall, a conservative Democrat, was on his feet, at the microphone: "You tell us all these grand things. Tell us what the federal deficit has been since Ronald Reagan took over. Tell us what the trade deficit is."

"If there was one hope, one commitment, Ronald Reagan wanted to keep," Fahrenkopf replied, "it was to balance the budget." He then blamed Congress for the size of the deficit, contending that if Congress had left Reagan budget proposals untouched, the deficit "would be $200 billion less than it is today . . . . Congress as an institution is incapable of keeping within its medians."

North Carolina state Rep. Bob R. Etheridge then demanded to know why Reagan has never sent a balanced budget to Congress: "If you don't send a balanced budget, how can you ever expect to have a reasonable spending program?"

Fahrenkopf then contended that if a balanced budget were enacted immediately, "there would be economic havoc . . . . You've got to work your way down in stages."

The Royall-Etheridge counters appeared to take the edge off Fahrenkopf's charge that liberal interest groups have "put a dog collar around the neck of the national Democratic Party," but he touched on one of the rawest nerves of local southern Democrats.

"Fahrenkopf's just a lot of gas," Alabama state Rep. Tom Butler (D), of Huntsville, said later, adding, however, "the national Democratic Party has gotten away from its center base" in support of a strong defense and sound fiscal policies.

Even Troy Brailey, a black state senator from Baltimore with strong ties to organized labor, said he agrees and thinks that the Democratic presidential nominee "is going to have to run on a conservative platform. It's sort of frightening to me, {but} I think it's the reality of the times."