Rep. Devin Nunes (R-Calif.) arrives for a closed House Republican Conference meeting on Capitol Hill in Washington, Dec. 19, 2017. (Aaron P. Bernstein/Reuters)

The House will attempt on Thursday to reauthorize and limit a controversial surveillance program that lets the government collect foreign intelligence on U.S. soil, without relying on the budget or other must-pass legislation to get it through Congress.

But significant political hurdles could derail the effort, as the bill members will vote on does not incorporate privacy protections that several lawmakers — including Republicans — have said are necessary to securing their support.

The measure, which House leaders published Tuesday evening, is a modification of a bill the House Intelligence Committee approved along party lines earlier this month. It renews the National Security Agency's authority to collect emails and other communications of overseas foreign targets from U.S. companies — an authority known as Section 702, named for the provision of the Foreign Intelligence Surveillance Amendments Act of 2008 that established it. But it limits the FBI's ability to view information contained in that database about Americans who may have been in touch with foreign targets.

The bill requires the FBI to get a court order before reviewing the content of queries it makes in criminal cases for information about Americans. The restriction would not apply to national security cases.

Support for the bill split along party lines in committee because Republicans included a provision changing the method by which the intelligence community identifies U.S. people on foreign surveillance reports — a process known as "unmasking." The legislation the House is expected to vote on Thursday removes that provision.

The amended House legislation also removes a controversial provision from the intelligence committee's bill redefining "foreign powers" and "agents of a foreign power," and appears to expand the situations in which communications "about" Americans, instead of directly to or from them, is prohibited. But it leaves in place a provision setting up a procedure for the government to restart collection of communications "about" U.S. persons after notifying Congress, if Congress does not act to prevent such collection within a 30-day window — a change likely to upset privacy advocates.

The intelligence community has identified a reauthorization of the Section 702 program as its highest legislative priority, and absent congressional action, it will expire at the end of 2017. But the House measure is expected to encounter opposition from privacy-minded lawmakers, including several in the House Freedom Caucus, who wanted more stringent restrictions on the FBI's ability to procure information about Americans contained in it.

Last month, the House Judiciary Committee endorsed a Section 702 measure that would have required the FBI to get a warrant before reviewing the contents of queries seeking evidence of a crime.

"The Judiciary Committee will be near-unanimous in its opposition to this bill, making it highly unlikely that it passes on the floor of the House," one congressional aide warned Tuesday night.

Such political realities are one reason some key Republicans cheered the decision to separate the Section 702 bill from the budget measure currently being debated in the House.

Rep. Thomas J. Rooney (R-Fla.), who chairs the House intelligence panel's subcommittee on the NSA and cybersecurity, noted Tuesday that "members of the Freedom Caucus and other libertarian types . . . have a problem with 702," adding he was glad to consider a reauthorization alone.

"They really shouldn't be included with each other," he said. "This needs to be debated by itself."

Should the Section 702 measure pass the House, it is unclear whether there is any road ahead for it in the Senate, where procedural requirements make it challenging to quickly pass a stand-alone bill.

The Senate Intelligence Committee endorsed a Section 702 bill in October that created only a procedural hurdle for the FBI to access information about Americans' communications in the database. That measure requires the FBI to submit a formal request to the Foreign Intelligence Surveillance Court to rule on the legality of any queries that turn up information about "a known United States person." The secret court considers any request for foreign intelligence or law enforcement purposes to be legal.

Senate leaders continued to stand by their proposal on Tuesday.

"I still believe that the Senate bill has much stronger protections," said intelligence committee vice chairman Mark R. Warner (D-Va.).

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Ellen Nakashima contributed to this report.