The House of Representatives passed legislation Thursday that would extend a controversial government spying power known as "Section 702" for another six years—without new privacy safeguards that had been sought by civil liberties groups.

Debate over the legislation now shifts over to the Senate, where it faces a filibuster threat from both Sen. Ron Wyden (D-Ore.) and Sen. Rand Paul (R-Ky.).

"If this Section 702 bill comes to the Senate, I will filibuster it," Wyden wrote in a tweet shortly after the House bill passed.

Wyden opposes the legislation because he believes that it offers too few protections for Americans' privacy rights. The powers granted by Section 702 are only supposed to be used against foreigners on foreign soil. But an American's communications can get swept up in the NSA's surveillance dragnet if they communicate with people overseas. Privacy advocates have championed an amendment to impose new privacy safeguards on the use of Section 702. But it was voted down by the House on Thursday.

The bill that passed the House enjoys support from Republican leaders in the Senate and is likely to get support from most Republican senators. But a few Republicans—including Paul and Sen. Mike Lee (R-Utah)—have expressed skepticism of unfettered NSA surveillance. And Wyden and Paul's filibuster threats mean that it will take 60 votes to pass the legislation.

As such, the bill will need support from as many as a dozen Democrats to pass the Senate.

When the Senate last renewed Section 702 in 2012, it passed by a 73-23 vote, with 19 Democrats, 3 Republicans, and independent Bernie Sanders voting no. But a lot has changed in the last five years. Barack Obama has been replaced by Donald Trump, potentially making Democrats more wary of handing broad surveillance powers to the executive branch.

There isn't much time for the Senate to act. Section 702 expires on January 19, a little more than a week away.