The House voted late Thursday to curb the National Security Agency's power to spy on Americans.
In a 293-123 vote, lawmakers approved an amendment to a defense appropriations bill that would bar the NSA from using any funds for two "backdoor" spying programs.
"That overwhelming vote changes the trajectory of this issue moving forward," Rep. Zoe Lofgren, a California Democrat who sponsored the amendment, said in an interview Friday.
The NSA has acknowledged that it sometimes spies on Americans' communications under a program intended to apply only to foreigners. The NSA scoops up vast batches of emails and other data from foreigners and then searches through that database, specifically looking for Americans' communications.
The amendment would require that the NSA obtain a warrant before reading Americans' private messages. The measure would also close another controversial NSA "backdoor" by cutting off funds for projects to build vulnerabilities into security products. The NSA exploits those vulnerabilities to hack into and spy on communications.
Rep. Thomas Massie, a Kentucky Republican, also spearheaded the amendment, which was cosponsored by lawmakers including Republican Reps. Jim Sensenbrenner and Justin Amash and Democratic Rep. John Conyers.