Washington — The Democrats' strategy for coping with President Reagan is simple: They are counting on a deteriorating economy that will so discredit the President that he will no longer be able to pull the public behind him.
At the moment the Democrats concede that Mr. Reagan retains his potent appeal. Thus, they are hoping to put together an alternative to Reagan's budget that will, in the end, receive the President's stamp of approval.
James Jones (D) of Oklahoma, powerful chairman of House Budget Committee, is a chief engineer of this project -- which he sees as a bipartisan effort.
This effort may be aided by Budget Director David Stockman's announcement that nearly $5 billion has been added to the projected deficit for fiscal year ' 83, raising it to $96.4 billion. Also fueling the search for alternatives are indications, as reported in Friday's Monitor, that the President is open to some ''revenue enhancements'' and other compromises.
Congressman Jones' approach, however, would touch what the President has declared off limits. Among other changes, he would want to cut the growth of military spending and add economic stimulants that bear a liberal stamp.
The Democrats now say there is a prospect that the Republican leadership, feeling that Reaganomics is working, will be willing to come together on a compromise budget alternative. And further, they hope that these same GOP leaders will be able to persuade the President to endorse a bipartisan effort.
Echoing other Democratic leaders, Mr. Jones says, as he did over breakfast on March 5, that ''the President still is the great communicator.'' He concedes that Reagan still may be able to go to the people, as he did last year, and rally a tremendous amount of public support for his budget.
But Jones also contends that rising unemployment, continued high interest rates, and the increased loss of confidence in Reagan among members of the business community may erode the President's credibility so that he no longer will be in the driver's seat.
When and if that moment comes, Jones and his Democratic colleagues see a bipartisan approach becoming attractive to both Republicans and the President -- and thereby winning out.
So the Democratic strategy has shifted from what it was last year. Then, although there was a Democratic alternative to the Reagan economic program, it really wasn't pushed that hard. And it faded in the face of the powerful GOP-Southern conservative coalition Reagan had behind him.
Therefore, much of the Democratic thrust last year was passive. The major Democratic theme at the time: Let's let Reagan have his program and then we can pick up the pieces -- and gain politically -- after it has gone awry. Sideline politics, some called it.
But now, becoming bolder as Reaganomics seems to be faltering, Democratic leadership on Capitol Hill is really seeking to make its own mark this year. It is ready to fight the President -- up to a point.
That is, it is willing to battle Reagan if it can get the Republicans to join in the fight -- in this bipartisan economic program.
Yet Republicans on the Hill are saying that the only kind of compromise program that the President might agree to would be one he would be able to call his own.
They say that Reagan, unless the economy and his credibility and leadership influence erode quickly in the next few months, isn't at all likely to accept the kind of bipartisan program that Jones is talking about.
Instead, they contend, Reagan would say ''no'' and accept a stalemate rather than take such an alternative -- and that he thereafter would seek to make the Democrats pay dearly by going to the public and blaming the Democrats in Congress for damaging the economy by not letting him put the final parts of his economic plan into place.
Thus, the Democratic strategy now is based on what they see as a growing public perception of a failed presidency -- and a bowed President who has to give up the initiative in dealing with the economy.
That's the moment -- should it arrive -- when this Democratic plan, which depends on being handed the initiative, begins to work.