Congressional Democrats outlined legislation Thursday aimed at undoing a recent Supreme Court decision that allows corporations and interest groups to spend freely on political advertising.

To accomplish that goal, the legislation would impose a patchwork of spending restrictions and disclosure requirements — many based in current laws.

The measure would greatly expand the scope of an existing ban on political commercials paid for by foreign corporations, ban political commercials paid for by government contractors or recipients of bailout money, and force corporations and unions to make public details of what they spend directly or through advocacy groups.

The legislation’s sponsors, Senator Charles E. Schumer of New York and Representative Chris Van Hollen of Maryland, said they wanted the measure enacted in time to limit the impact of the court’s decision in the case, Citizens United vs. the Federal Election Commission, before the fall campaigns. “Otherwise the court will have predetermined the winner of the midterm elections,” Mr. Schumer said. “It won’t be the Republicans or the Democrats. It will be corporate America.”

Many of the proposals, like restrictions on foreign companies or government contractors, have populist appeal, but passage would require the vote of at least one Republican senator. Five current Republican senators — led at the time by Senator John McCain of Arizona — voted for the spending rules that the court chipped away, but not one has yet embraced the Democrats’ proposals.

The sponsors said they had developed the legislation to comply with the court’s opinion in Citizens United.