The draft bill which is expected to put an end to graduate deferments passed its last major hurdle yesterday when the Senate okayed it, 72-23.

The bill now goes to the House, where it is expected to pass easily.

The measure does not specifically end graduate deferments, but it gives President Johnson the authority to decide which deferments are necessary. The President has already stated he favors eliminating all graduate deferments except for medical, dental, and divinity students.

But the cut in deferments is not expected to affect the college graduating class of 1967. It will take at least six months for the Executive to draw up the new regulations governing deferment.

The bill would bar the President frame setting up a draft lottery -- which could be rough to set unless he goes to Congress for separate authorizing legislation. The blow to the lottery set off Senate opposition to the bill led by Sen. Edward M. Kennedy. (D-Mass.)

Instead of random selection by lottery, the bill re-establishes the present system of drafting by date of birth within age groups. But the priority of the age groups will be reversed. The youngest -- 19-year olds -- will be the first to go, whereas the oldest are now taken first.

All college students will be deferred for the duration of their undergraduate careers provided only that their work meets the standards of their schools. This will, of course, eliminate the draft tests and class rankings used in the past by local boards to call out some students for the army.

Present undergraduates will go into the "prime age pool with the 19-year olds upon graduation.

The bill also narrows the basis for conscientious objection, Kennedy claimed. An aide said its provisions make orthodox religious belief a prerequisite of CO classification.