Supporters and opponents of a major piece of anti-piracy legislation jockeyed to bolster their positions on Monday, with a key critic in the Senate vowing to filibuster and the music industry releasing an analysis showing that the bill enjoys bipartisan support in a year of gridlock.

The legislation in the House and the Senate is aimed at curbing so-called “rogue” websites overseas that traffic in pirated goods, including movies, TV shows and music.

But critics say that the bill is written too broadly, and warn of unintended consequences if the government seeks court orders forcing Internet providers to block domain names and search engines to disable links.

Chief among the opponents in the Senate is Sen. Ron Wyden (D-Oregon), who put a hold on the bill shortly after it passed the Senate Judiciary Committee unanimously in May. On Monday, Wyden appeared in a video for the progressive org DemandProgress in which he said he said that he planned a filibuster and, as part of such an action, would read from the floor of the Senate the names of those who signed a petition opposing the legislation.

“Congress needs to hear from more than the lobbyists who wrote this bill, Congress needs to hear from people like you who understand the value of a free and fair Internet,” Wyden said.

On the other side of the debate, the Recording Industry Assn. of America released an analysis they said “underscores the unique nature of the broad, bipartisan support” for the legislation in the Senate. Of the 1,882 bills that have been introduced in the Senate so far this session, only 31 other bills enjoy the support of 35 or more cosponsors. Of those 31, only 18 enjoy “substantial bipartisan support.” The Senate bill, called the Protect IP Act, has 39 co-sponsors from both parties.