Washington (CNN)Some members of Congress are scrambling to find a way to make sure the National Security Agency's bulk collection of data continues before the program is shut down.
Congress mulls how to keep NSA program from going dark
But they better hurry up: The program is set to go dark on June 1, and Congress is getting ready for a week-long Memorial Day recess despite the lack of resolution to a matter many feel is critical to national security.
Last week, the House overwhelmingly passed the USA Freedom Act, which would shift responsibility for holding data from the government to telecommunications companies while also imposing stricter limitations on how authorities could access the information.
Senate Majority Leader Mitch McConnell, however, is pushing for a two-month extension of the current law.
The Senate is preparing to vote on both the House's bill and an extension either Friday or Saturday, but Intelligence Committee Chairman Richard Burr, R-North Carolina, said he expects both of those to fail.
California Democratic Sen. Dianne Feinstein, the top Democrat on the Intelligence Committee, said she was preparing a backup proposal in the event that the two NSA votes failed, but she wasn't ready to concede on Thursday night that the USA Freedom Act would be defeated in the Senate.
"I think it's coming close to passing," Feinstein said.
Burr told reporters he planned to unveil new legislation on Friday that would make some changes to the program, and said he took some concepts from the House bill.
Burr's plan would provide a two-year transition for telecommunications carriers to take in the bulk data and store it, and would require them to update Congress on their efforts.
But he admitted his bill won't get a vote before the June 1 deadline, and said options being discussed by Senate leaders about a short-term extension of the current law ranged from "anywhere from five days to four weeks."
Maine Independent Sen. Angus King told CNN on Thursday that there are "productive discussions" about possible alternatives to the House bill or an extension, but he also conceded that "it's going to take some time."
"Right now, it's anybody's guess where the votes are," he said.
If the Senate does approve a short-term bill, there would be intense pressure on the House to accept it quickly, because members will have already left Washington for the recess and aren't scheduled to return until June 1 -- the day the NSA's current authority lapses.
On Thursday, House Speaker John Boehner urged the Senate to act, and admitted he was surprised by the "big disconnect" in terms of how the Senate viewed the House deal.
But he didn't rule out the Senate potentially sending the House a straight extension of the law.
"If they act, we'll take -- certainly look at what they do and make a decision about how to proceed," Boehner said.
But getting the votes to pass a bill that continues the NSA program without any changes -- even for a brief period of time -- could be a heavy lift in the House. There is a bloc of libertarian conservatives on the right and progressive Democrats on the left who strongly oppose the current law.
Three House Democrats and three House Republicans sent a letter to Boehner and House Democratic Leader Nancy Pelosi on Thursday afternoon noting a recent court ruling striking down key provisions of the law. They vowed to oppose any short-term bill, saying, "a vote on a clean authorization of this authority without real reforms would be a disservice to the hundreds of millions of Americans we represent."
The Justice Department has already circulated a memo on Capitol Hill warning that it would have to start winding down parts of the program as soon as Friday if Congress can't find agreement on some type of renewal.
"After May 22, 2015, the National Security Agency will need to begin taking steps to wind down the bulk telephone metadata program in anticipation of a possible sunset in order to ensure that it does not engage in any unauthorized collection or use of the metadata," the memo states.
The second highest-ranking Senate Republican, Sen. John Cornyn of Texas, told reporters Thursday that "nobody wants us to go dark on our ability to detect terrorist activity," but said he didn't know how Congress would prevent that from happening.