WASHINGTON — Two leading Democrats introduced legislation Thursday to blunt the impact of a US Supreme Court decision last month giving corporations free rein for unlimited campaign spending.

The bill by Senator Charles Schumer and Representative Chris Van Hollen would restore some of the decades-old restrictions on corporate campaign spending overturned by the court last month.

The legislation would bar foreign corporations, government contractors and companies that have received government assistance from election spending expenditures, and would require top corporate executives to appear on screen to issue the disclaimer that typically runs at the end of US campaign ads.

Schumer said the bill is meant to prevent corporations from gaining too much influence in the US electoral process.

"The Supreme Court shattered nearly a century of US law curbing the influence of corporations in our election process. With this bill, we are beginning to pick up the pieces," he said.

"At a time when Americans are worried about special interests having too much influence, the court's ruling opened the floodgates for corporate money to pour into our election process."

Schumer said the bill also would strengthen a candidate's ability to respond to corporate attack ads, allowing them to purchase air time at the lowest possible rate in the same media markets, and also will prevent private corporations from coordinating their political activities with candidates.

The Supreme Court's 5-4 decision held that corporations could dip freely into their general funds to finance campaign ads either in support or against a particular political candidate.

The ruling is expected to result in an even more intense barrage of campaign ads than usual in the run-up to mid-term congressional elections later this year, and President Barack Obama's 2012 re-election race.

Shortly after the ruling, Obama warned that "the Supreme Court has given a green light to a new stampede of special interest money in our politics."