The bill "would do very little to improve our country's national security," he said. "In fact, in its present form, I believe the bill before us would do more to harm our country's economy and expand the size and influence of the federal government -- specifically the Department of Homeland Security -- than anything else."

Other Republicans are asking for the Senate leadership to allow a vote on the , a controversial health-care bill, in exchange for a vote on the cybersecurity bill.

Senator Mark Udall, a Colorado Democrat, criticized Republicans for holding up the bill. "I believe the bill is long overdue, and we simply cannot afford not to act," he said on the Senate floor Wednesday.

Another group of senators, mostly Democrats, have pushed for an amendment to remove provisions that would allow ISPs and other Web companies to monitor their customers' online activities and take countermeasures against cyberthreats. The provision would protect the ISPs and other companies against customer privacy lawsuits.

Fifteen senators, led by Senator Al Franken, a Minnesota Democrat, are pushing for the amendment. The bill, as written, would violate Internet users' privacy, Franken said.