The House is set to vote Thursday on a bill to extend the electronic surveillance powers of the National Security Agency. 

How the House votes could determine whether the bill wins Senate passage for a long-term extension of provisions of the Foreign Intelligence Surveillance Act, or if lawmakers hit another roadblock and decide to punt again. Facing an impasse before Christmas, Congress passed a short-term extension until Jan. 19. The provisions were due to expire Dec. 31. 

Current law allows U.S. spy agencies to conduct electronic surveillance on foreign persons. Section 702 of FISA empowers the National Security Agency under a special court order to collect and analyze emails and other digital communications of foreigners living overseas, but the agency also ends up collecting data on an unknown number of U.S. persons, which it can later search without a warrant.

Once again, lawmakers sympathetic to the intelligence community, whom Democratic Sen. Ron Wyden of Oregon calls the “status quo club,” are facing off against a surprisingly strong bipartisan group from both chambers of Congress that is demanding tougher privacy protections and measures to rein in surveillance powers.

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The pro-privacy protection group includes Republicans such as Freedom Caucus leader Mark Meadows, Tea Party member Justin Amash and Rep. Ted Poe, along with Democratic Reps. Zoe Lofgren and Jerrold Nadler. It also includes Republican Sens. Rand Paul and Steve Daines.

On Tuesday, the House Rules Committee decided to allow debate on an amendment backed by a contingent of 40 lawmakers led by Amash and Lofgren. The amendment would require the FBI to obtain a warrant before it begins searching the NSA’s surveillance database for information on American citizens. 

The group is pushing back against legislation passed by the House Intelligence Committee that would require a warrant only if the information the FBI obtains is to be used in a criminal proceeding — a bar that Amash, Lofgren and Nadler say is so low that it is meaningless. 

Lofgren also is sounding the alarm on the scope of collection. Unlike the 2015 clash among lawmakers on provisions of the Patriot Act that revolved around intelligence agencies being able to collect metadata on Americans’ phone calls — data that showed who called whom, when and for how long, but not the content — the current debate involves content of calls and emails. 

While the scope of what the NSA’s surveillance database includes is classified, “it’s a lot of information,” Lofgren said at a news conference on Wednesday. The database has “vast amounts of information, content from calls, images, and videos” of Americans, the California Democrat said. Allowing the FBI to begin searching the database without first seeking a probable cause warrant would be a violation of rights guaranteed under the Constitution’s Fourth Amendment, she said. 

If the Amash amendment fails and the House backs the less restrictive version, the legislation could potentially fail in the Senate. At a news conference on Wednesday, Paul said he would filibuster the surveillance bill if it did not include tough warrant requirements. 

If lawmakers fail to reach agreement, it is likely Congress will pass another short-term extension of the current law. 

Even if Congress dawdles, “they will not go dark,” Lofgren said about the intelligence agencies. The secret court order that authorizes the NSA to conduct surveillance is valid for 12 months, and the last one was issued in April 2017. 

Some see the Section 702 surveillance as part of a larger trend. A report released by Human Rights Watch this week documents how the federal government and local police departments around the country are using technologies to gather evidence, identify and arrest suspects and then try to recreate evidence using more public means, in an effort known as “parallel construction.”