WASHINGTON – Congress narrowly passed a $2.6 trillion budget yesterday that would cut back spending on the Medicaid health-care program for the first time since 1997 in a step toward trimming federal deficits.

The Senate voted 52-47 to approve the blueprint of tax and spending priorities just hours after the House passed it by a similarly close 214-211. The budget instructs lawmakers to freeze or shrink spending in many domestic programs outside defense and homeland security, and to restrain farm, student loan, pension, and some other government programs that grow automatically from year to year.

House Majority Leader Tom DeLay, a Republican of Texas, said it’s time to look closely at benefit programs that are “popular but rife with waste.”

“These entitlement programs deserve reform,” he said. “The Medicaid system is antiquated, and the quality of care is not being brought to the people that need it.”

The budget sketches out plans and priorities for spending $2.6 trillion in the fiscal year that begins October 1, projecting a federal deficit of $383 billion. Lawmakers use the blueprint to pass specific tax and spending legislation later in the year.

After the House vote, President Bush praised the budget resolution. “This is a responsible budget that reins in spending to limits not seen in years,” he said in a written statement.

Democrats denounced the proposed cuts.

“This budget is a missed opportunity because instead of being a blueprint of positive initiatives for the future, this budget is an assault on our values,” the House Democratic leader, Nancy Pelosi of California, said.

Republicans said the plan to shrink federal spending only nicks rapidly growing benefit programs, which will continue growing but at a slightly slower rate.

Senator Grassley, a Republican from Iowa and chairman of the Senate Finance Committee, committed not to eliminate coverage for the needy and disabled Americans covered by Medicaid, the health-care program run jointly by state and federal governments.

“Doing nothing is far worse for Medicaid beneficiaries,” Mr. Grassley said.

Democrats expressed skepticism about GOP promises and questioned the budget’s projections of shrinking deficits. “This budget says the lives of poor mothers and poor children are not that important after all,” said Senator Kennedy, a Democrat of Massachusetts. “Under this budget, tax breaks for the rich are more important than life itself.”

The budget would shave automatically increasing benefit programs by $35 billion over five years while also cutting taxes by as much as $106 billion over the same period.

Medicaid gets marked for a $10 billion reduction over four years. The changes in Medicaid wouldn’t begin until 2007, giving a specially convened commission and the nation’s governors time to recommend cost-saving proposals.