Democrats: an echo not a choice

''But where is our alternative?'' This question, posed by Senator Fritz Hollings at the Democratic mini-convention in Philadelphia, got to the bottom of the Democrats' problem: They simply aren't able - or willing - to offer the voters a clear-cut choice.

Certainly there will be Democratic gains this fall, as a result of a growing dissatisfaction with Reaganomics and of the normal reaction that takes place in off-presidential-year elections.

But Democrats in Congress have joined with the Republicans to put through what is a substantial shift away from the traditional spending approach to government - away from the FDR thrust.

And, as Hollings says, the Democrats have not come up with any legislative alternative to the Reagan approach. The reason: every time they go back and talk to the voters they find that too many of their supporters still like the President and don't want him kept from moving his economic initiatives forward.

The basic element of the Democratic argument to be taken to the voters this fall - and, it seems, in 1984 - is becoming known. It is not ''Let's change course.'' Instead, it is ''Let's make some adjustments to the Reagan program.''

If Barry Goldwater were a Democrat and assessing the Democratic political strategy, he would doubtless say that the Democrats were offering the voters an echo, not a choice. There is indeed a strong strain of me-too-ism in the Democratic political philosophy today.

Pollster Peter Hart, who represents several Democratic candidates, is telling his clients that they will not pick up votes by saying ''no'' to Ronald Reagan. In talking with reporters recently, Mr. Hart said that he counselled Democrats seeking election to say that they want to make ''adjustments'' to the Reagan program.

In Philadelphia it became clear that the influential Democratic politicians assembled there were adopting the Hart thesis: win not by confronting the popular Reagan but by telling the voters that if elected you will help steer the Reagan program in a more useful, fairer direction.

Senator Kennedy, who got the most applause in Philadelphia, spoke to the me-too-ism problem. ''The last thing this nation needs in the 1980s,'' he said, ''is two Republican parties.''

Kennedy as of now clearly represents an alternative: the old-time Democratic political religion that critics describe as a process of throwing money at a problem in order to solve it. But Kennedy as a Senator has not been able to counter the thrust of Democratic me-too-ism in Congress. And there is much evidence that the Democratic Party isn't willing to go to the polls with a direct challenge to Reagan's opposition to big government and big government spending.

Is the Democratic Party ready to nominate a liberal Kennedy? It doesn't seem likely. Democratic leaders are saying he must ''modify'' his liberalism if he is going to be able to win the nomination.

And what of the other potential candidates? Walter Mon-dale calls Reaganomics ''radical and wrong.'' But his formula seeks to make the Reagan approach ''fairer.''

John Glenn also castigates the Reagan record. But his recommendations call more for improving the Reagan approach than for adopting a whole new - or old - alternative.

Alan Cranston says that the Democrats ''must promise - and produce - a different, better future and make it work.'' But he doesn't say how they ''must not offer the solutions of the 1930s or the 1960s for the problems of the 1980 s.''

Gary Hart says that the Democrats ''have always been the party of ideas, and progress, and movement, and change.'' But beyond making the current conservative approach to governing more equitable, he doesn't supply the clear alternative that Hollings says is lacking.

Thus the question posed by Hollings, who is also a candidate, but who seems to have very little Democratic support, remains: Can the Democrats move back into full power with only an echo - and no clear-cut choice?