If one of the Democratic presidential hopefuls were in the White House today, Congress would probably be looking at a more ambitious jobs program than the one President Reagan has indicated he will sign.

Four of the six Democratic candidates would go beyond the $4.9 billion package passed by the House and pending in the Senate, doubling its scale in the case of Sen. Alan Cranston (Calif.), and adding to its scope in the cases of former Florida governor Reubin Askew, Sen. Gary Hart (Colo.) and former vice president Walter F. Mondale.

Sen. Ernest F. Hollings (S.C.), on the other hand, said a budget freeze would produce many more jobs than any jobs bill, and Sen. John Glenn (Ohio), while saying emergency legislation "is urgently needed," said any jobs bill could assist "only a small number of people."

The six active declared and undeclared Democratic presidential hopefuls responded Friday to a question from The Washington Post on what kind of jobs legislation and assistance to the unemployed they would recommend if they were in the presidency today. A seventh potential but unannounced candidate, Sen. Dale Bumpers (Ark.), declined to answer.

All of the candidates except Glenn and Hollings indicated that, despite budget constraints that they acknowledged, they found Reagan's limits on the jobs package too restrictive.

Cranston called for a $10 billion program aimed at creating 1 million public jobs. Askew said, "I would be willing to spend more than the $4.3 billion proposed by President Reagan." Hart said Reagan's program "is not enough." Mondale commented that "the jobs bill now before Congress should be larger--as it would have been without the president's veto threat."

By contrast, Glenn and Hollings put heavier emphasis on reducing deficts as the key to sustained recovery and described a more limited role for the jobs program. Glenn said "burgeoning deficits" will keep unemployment "unacceptably high,"

This is the first in a series of occasional articles on presidential candidates' positions on major issues. unless more basic changes are made in the Reagan economic program. Hollings said, "The best emergency jobs program is my budget freeze."

Congress is legislating in this area with the knowledge that Reagan has frequently criticized "make-work" programs as wasteful and counterproductive. He threatened to veto a $5.4 billion jobs bill passed by the House last December but said through aides last month that he would go along with a slightly smaller program negotiated by White House assistants and the House Democratic leadership.

That bill was passed by the House March 3 and, in slightly scaled-down form, was moving through the Senate when it was snagged Thursday by a dispute over withholding income taxes on dividends and interest.

On Friday, Senate Democrats tried unsuccessfully to add $1.7 billion to the measure for jobs and food, shelter and health programs for the unemployed. Glenn and Bumpers voted for the amendment; Hollings, Hart and Cranston were out of town campaigning.

In addition to their differences with Reagan on the scale of the program, the Democratic candidates offered various suggestions that would change the emphasis or direction of the jobs program being crafted to meet the president's criteria.

While most of the emphasis was on going beyond the pending legislation, there were occasional proposals to put limits on the pending bill.

Askew said, for example, that in view of the unemployment emergency, he would be willing to "exempt this relief bill from the 'prevailing wage' provision of the Davis-Bacon Act," if convinced it would create more jobs. Organized labor is a staunch defender of the Davis-Bacon provisions, and the House-passed bill does not disturb them.

Just as their current views diverge slightly, so do the voting records of the five senators, including Bumpers, who served in the Senate during the last six years.

Last year, Hollings split from the others in opposing an amendment to the balanced-budget constitutional amendment allowing deficit spending when necessary to keep unemployment from exceeding 10 percent. Last May, Hart was the only one of the group to support an unsuccessful amendment by Sen. Edward M. Kennedy (D-Mass.) to add $2.5 billion in the budget resolution for a targeted jobs program.

A year earlier, in 1981, when Reagan was newly in office and the recession was beginning, Hollings and Glenn split from the others in opposing some key job-related amendments.

Hollings voted against amendments to the budget reconciliation measure expanding youth training and unemployment insurance funds and making room for a pilot program in private-sector employment sponsored by Glenn.

Glenn broke with the other four in opposing a Kennedy amendment to restore $120 million in funds for unemployment compensation administration and opposed another amendment to provide $300 million for demonstration programs in CETA youth employment.

In 1977, all five supported the public works jobs program that was part of President Carter's original economic stimulus package and voted to extend unemployment compensation during that recession. On several occasions between 1977 and 1979, Hollings and Bumpers voted for cuts in CETA funds opposed by the other three. But all five voted to keep the CETA program going in 1978.

As vice president, Mondale headed the White House task force on youth employment, which led to the Youth Employment Act of 1980, and lobbied for other job-related public works programs.

As governor of Florida, Askew created a Department of Labor and Employment Security and put heavy emphasis on an apprenticeship program aimed at reducing youth unemployment.