As Vice President Bush stood on a podium in the chancellery groping for a phrase to describe his morning session with West German leader Helmut Kohl, he committed a slip of the tongue that spoke volumes about an important dimension of his trip here last week.

Bush characterized the 90-minute discussion as a "warm and friendly candidate" when he meant to say "candid," provoking a broad grin from Kohl and guffaws from assembled journalists.

The subconscious allusion to the Reagan administration's ardent wish to see Kohl confirmed as chancellor in March 6 elections underscored the perception in foreign capitals that the vote may influence the future of European security as well as relations between the superpowers.

The campaign has been dominated so far by the prospects of deploying 572 Pershing II and cruise missiles in West Germany and four other West European countries if arms control talks in Geneva between the United States and the Soviet Union fail to achieve an agreement restricting intermediate-range nuclear weapons in Europe.

Kohl has stoutly defended the "zero option" proposed by Washington that offers to cancel deployment of new missiles if the Soviet Union scraps its arsenal of nuclear-tipped rockets aimed at Western Europe.

The opposition candidate for chancellor, Social Democrat Hans-Jochen Vogel, has argued that French and British independent nuclear forces should be taken into account to reach a more realistic compromise, one that would "radically reduce" the number of Soviet weapons to a level that would nullify the need to base the modern nuclear missiles on European soil.

Vogel has sought to depict the choice before voters as one of Kohl wanting a mandate to install the Pershing II and cruise weapons in West Germany while he seeks a mandate to keep them out.

The international repercussions of such conflicting approaches have been felt so strongly among Bonn's allies and neighbors that the election has assumed overtones of a referendum that will determine West Germany's status in the Atlantic Alliance and the world at large.

The global impact of the missile campaign has overshadowed debate about the weakness of the German economy and record unemployment of nearly 2.5 million, which in normal times would captivate the minds of voters and still may ultimately affect the outcome in the polls.

While West German voters have evinced few signs that they are being swayed by the pleas and preferences of foreign voices, the propaganda war waged from abroad seems likely to intensify and may influence voting trends as the campaign enters its climactic weeks.

Soviet Foreign Minister Andrei Gromyko, in a state visit here three weeks ago, urged his hosts "to follow their own interests" and remember that in the nuclear age, "West Germany and the Soviet Union are, figuratively speaking, in the same boat."

Since then, Moscow has continued to press its message on the German public, publicizing a call to establish a nuclear-free zone in Central Europe and dispatching lobbyists who have been appearing at West German universities at the rate of 20 a month.

The Soviets also have muffled their early advocacy of Vogel, who was warmly received on a trip to Moscow last month by Soviet Communist Party leader Yuri Andropov. The Christian Democrats pounced on that event to impugn Vogel's allegiance to the western alliance and to describe him as "the Andropov candidate."

Vogel has effectively rebuffed such charges through his calm, professorial demeanor and meetings with western leaders, including President Reagan and Bush, to whom he vowed that a Social Democratic government in Bonn would fulfill allied commitments in "a loyal and reliable manner."

Nonetheless, a gnawing concern that Vogel would eventually bow to public and party opposition to the missiles and prevent deployment later this year has stimulated support for Kohl in Washington, London and Paris.

Kohl has emerged as the obvious favorite among governments in those three capitals less for any leadership qualities or ideological compatibility than for the perception that a Christian Democratic chancellor offers the best hope to counter neutralist and pacifist forces in West Germany.

Despite Vogel's efforts to reassure Bush, U.S. diplomats admitted that Kohl sounded more convincing when he was quoted as telling the vice president that "our place is at the side of our allies, for Germans are not wanderers between the two worlds."

In a speech before the Bundestag, or lower house of Parliament, last month marking the 20th anniversary of the French-German friendship treaty, French President Francois Mitterrand gave a resounding pat on the back to Kohl by endorsing the "zero-option" proposal and warning about any attempts to "uncouple" the security of Western Europe from the United States.

Despite sharing socialist credentials, Mitterrand and Vogel differ strongly about counting French and British nuclear deterrent systems in any overall assessment of the arms balance in Europe.

On Friday, Kohl visited British Prime Minister Margaret Thatcher at her country retreat, Chequers, and later stressed their joint conviction that the Soviet Union must not be allowed to maintain a monopoly in medium-range nuclear missiles.

At the same time, in an apparent bid to reassure voters that the West was amenable to compromise in the arms talks, the two leaders said that the "zero option" remained a final goal but did not represent "a take-it-or-leave-it proposal."

In recent weeks, Kohl has shown more sensitivity to voter concern that the U.S. position was too inflexible and has drifted toward the view of his foreign minister, Hans-Dietrich Genscher, that partial disarmament through an "interim solution" is better than no agreement at all.

Kohl also has taken pains to emphasize the urgent need to improve relations between the superpowers through a summit between Reagan and Andropov.

In an apparent effort to show that he, too, is prepared to serve as an interlocutor between the United States and the Soviet Union, Kohl announced on Friday that he intended to visit Moscow in the near future if he is reaffirmed as chancellor in the March election.