The strong anti-SALT II position taken by Senate Minority Leader Howard H. Baker Jr. (R-Tenn.) could prove helpful, not damaging, in his unannounced drive for the Republican presidential nomination in 1980, according to a national Washington Post poll of Republican Party activists.

In fact, the Poll suggests, an argument may be made that Baker virtually had to come out against the strategic arms limitation treaty (SALT II) to improve his standing among party workers nationwide.

Baker, in criticizing the treaty agreed upon by President Carter and the Soviet Union, said Wednesday that he was taking his position as a matter of principle.

The politically popular position for a presidential aspirant would have been to support the treaty, he said, because most polls show that a majority of Americans support it.

That may be true among the public, although polls offer conflicting estimates of how Americans feel about SALT II.

However, according to The Post poll, it is decidely untrue among people that any Republican presidential candidate must go to for support: party workers and activities. They are, judging from the poll, against a treaty with the Soviets and overwhelmingly in favor of a get-tough attitude toward the Soviet Union.

Futhermore, until now they appear to have shown little or no sign of approving Baker as their party's nominee in 1980.

The Post interviewed 1,310 delegates to the 1976 Republican National Convention by mail in May. Only 6 percent listed Baker as their choice for 1980. He placed far behind Ronald Reagan and John Connally, and slightly behind George Bush and Philip Crane.

Baker did substantially better in a nationwide telephone poll by The Post that was taken at the same time, placing second only to Reagan among people who said they were Republicans.

At this stage in a presidential campaign, however, most political observers tend to discount public sentiment, and stress activity within the party. It is from the activists, people like the delegates, that local campaign organizations are formed, money raised, and later on, much opinion molded.

The Post asked Republican delegates three questions that might have some bearing on their attitudes toward Salt II. The first had to do with military spending, and, by 7 to 1, the Republican delegates said the United States could not meet its national security obligations "with a much smaller defense budget than we have now."

The second asked whether the United States should "try harder to relax tensions with Russia, or should the U.S. get tougher in its dealings with Russia." By 72 to 17, with 11 percent uncertain, the Republican delegates took the get-tough position.

The third question asked whether the United States should try to maintain military superiority over the Soviet Union or work for an arms limitation treaty that would leave the two countries "as equal as possible militarily."

Some Republican delegates took issue with that question, saying the United States could "maintain" superiority because we are not superior now. Some others said Salt II does not provide equality. Overall, they came out in favor of superiority over equality by 73 to 23 with 4 percent undecided.

Baker's criticism of SALT II, it would appear, puts him in line with the people whose political assistance he needs the most right now. His approval of the treaty would have had the opposite effect.