When more than 10 million Americans voted for a nuclear arms freeze Nov. 2, it may have looked like the end of a race. In fact, it was the beginning of a marathon.
Buoyed by their substantial election successes, organizers of the nation's growing peace movement are asking, ''What is the next step?'' as they look down the long road to their goal of ending the nuclear arms race.
''We're only 1 percent along the way,'' says Dr. Helen Caldicott, founder of Physicians for Social Responsibility and an early freeze activist. In the fight to rid the world of nuclear weapons, she adds, ''the freeze (vote) is only a blip.''
In many ways, some activists agree, the battle now becomes a tougher one. They note that opponents to the freeze - including groups like Moral Majority - have begun to organize and grow. They also say the campaign must deepen its hold at the grass-roots level, and it faces the crucial task of educating voters about the movement's view of the more complex issues of the arms race.
''The freeze was great because it was so simple everyone could understand it, '' says a spokesperson for the Union of Concerned Scientists (UCS). ''But obviously, we can't just operate from a freeze mentality.''
The areas where anti-arms race organizers are now planning ''next steps'' include:
Politics. One of the first items on the freeze activists' agenda is the introduction of a new freeze resolution in the US House, similar to a measure defeated there by only two votes - and intensive Reagan administration lobbying - last August. With the election of several new apparently pro-freeze congressmen, organizers say they expect such a resolution to pass (although it would appear bound for defeat in the Republican-controlled Senate).
Despite the Nov. 2 vote, White House spokesman Larry Speakes says the President believes the American people support his catch-up-then-reduce arms proposals. Still, some observers warn, Mr. Reagan may find himself in political trouble if he doesn't alter his defense course.
''Reagan has to be very, very cautious,'' argues Dr. Sheldon Kamieniecki, an assistant professor of political science at the University of Southern California. ''He's going to have a lot of soul-searching to do, political and otherwise. He can't ignore (the freeze vote).''
In addition to pushing for a new freeze resolution in the House, activists say they plan to lobby against coming appropriations for weapons such as the MX missile and the medium-range Pershing II. These missiles, they argue, could be used for a first strike and would be nonverifiable under a freeze agreement.
''If we can't get a freeze in place,'' says Tim Button, state coordinator of Iowa's freeze campaign, ''we have to take away the money for the weapons.''
Education. Already, several state campaigns have begun to focus on education programs aimed at explaining their view of the complexities of nuclear weapons policy and the connection between defense spending and the economy. Conferences and teach-ins also are being planned.
To get people thinking beyond the freeze, the UCS, for example, is sponsoring teach-ins at 500 college campuses this week. The debates, public forums, and panel discussions will highlight the salient issues in the nuclear weapons debate such as a comprehensive test-ban treaty and the ''no first use'' concept.
''We're taking the awareness that came about as a result of the freeze campaign and trying to use that to get into truly educating people on the arms race and disarmament,'' says John Schlaefer, a spokesman for the freeze campaign in Wisconsin, where 75.8 percent of the voters approved a freeze measure in the state's September primary election.
''We want people to be more than aware,'' he explains. ''We want them to have the knowledge they need to make decisions on arms policy, to talk to their congressmen.''
Religion. The mushrooming involvement of mainstream churches in the peace movement is expected to continue growing as congregations pursue ''peace projects'' set to last as long as five years.
''This isn't just a political issue, for the churches it's a moral one,'' says a spokesman at the Interfaith Center to Reverse the Arms Race, an ecumenical organization in Pasadena, Calif. ''We're in this to the end.''
Already, at least one major religious peace conference has been announced: ''The Church and Peacemaking in the Nuclear Age, A Conference on Biblical Perspectives,'' to be held next May. In addition, Roman Catholic bishops have generated a widespread controversy through their draft of a pastoral letter on nuclear arms issues.
But as freeze activists contemplate their next steps, so do freeze opponents. In California, where the freeze passed by a narrow margin of 52 to 48 percent, a spokesman for Californians for a Strong America, which opposed the freeze, says efforts to organize opposition to the freeze movement will continue into the 1984 elections.
Other conservative groups, including the Moral Majority, also have announced plans to wage ''anti-freeze-nik'' campaigns. Phyllis Schlafly, who helped lead conservative opposition to the Equal Rights Amendment, says her group, The Eagle Forum, will wage an educational campaign against the freeze.
''We plan to show the fraudulent nature of the freeze movement,'' she says. ''These groups promote pacifism, therefore they promote war. History shows that peace movements only bring on war.''