Admirers of unblushing boldness have to respect our leading national teachers' union for billing itself as the National Education Association. (Not even the pushy folks at the AMA would dare call themselves the American Health Association.) In politics, where the NEA has shown similar nerve, the union's endorsement -- especially because of its articulate and college-educated membership -- is coveted and pursued mostly by Democratic candidates.

In 1976, Jimmy Carter committed himself to the creation of a department of education and the NEA committed itself to Carter. At the 1980 Democratic convention, the largest and most influential delegation belonged not to California, but to the NEA, which put 311 of its members on the floor as delegates and five pages of its program into the party platform.

However, the problem with endorsements of any candidate by any union or other organization is that they frequently mean a lot more to the candidate than to the endorsing group's membership. Take the case of 1980, when the NEA endorsed Carter for reelection. In November, the NEA membership, according to the union's own study, voted for Carter over Reagan by only 44 to 40 percent.

The truth is that the vote for president is the most personal vote any citizen casts. We generally feel quite competent to make our own decisions about the candidates without relying for guidance upon our employer or our shop steward. In fact, at a time when public approval of labor unions is at its lowest point since 1936, according to the Gallup Poll, union leaders are judged to have the lowest ethical standards of any occupation group except the much-abused car salesmen.

Endorsements are signposts for voters; not all signposts are positive. If a teachers' group, for example, were to endorse a Democratic presidental candidate after that candidate had emphatically opposed competency testing for public school teachers, then it might be a lot of fun to be running against that endorsed candidate. Or how about the candidate who is not endorsed by the AFL-CIO and who has the imagination to go to a local labor meeting in Manchester, N.H., and say: "I don't believe anyone can tell you how to vote. You are free and independent and capable of making up your own mind. You don't need anyone in a $600 suit and a pinky ring, from an air-conditioned limo or Miami Beach hotel suite telling you who you have to vote for."

An endorsement can mean a lot to voters in a low- informational contest like a race for county commissioner or state auditor. But endorsements don't mean much in presidential campaigns.