According to a Wednesday morning Senate whip notice, S. 990 will also be the legislative vehicle for the Patriot Act extension. A Tuesday filibuster from Sen. Rand PaulRand PaulOvernight Defense: General says US strike probably led to civilian deaths | Tillerson to push NATO on spending | Trump taps F-35 chief Senate backs Montenegro's NATO membership We need congressional debate on Yemen MORE (R-Ky.) prevented the Senate from taking up the Patriot Act extension by itself.

Instead, the Senate will take up several amendments to S. 990 from Senate Majority Leader Harry ReidHarry ReidRepublican failure Senate about to enter 'nuclear option' death spiral Top GOP senator: 'Tragic mistake' if Democrats try to block Gorsuch MORE (D-Nev.) on Wednesday. The key amendment would add to S. 990 the Patriot Act extension language, allowing U.S. intelligence officials to conduct roving wiretaps, access business records, and conduct "lone wolf" surveillance until June 1, 2015.

Reid on Tuesday filed for cloture on the bill, which should allow the Senate to vote on the package on Thursday. Reid's effort was aimed at avoiding Paul's filibuster and amendments to the Patriot Act bill that he wanted to pursue.

Assuming the Senate can pass the bill Thursday, the House would have to quickly act on the same bill in order to avoid having the Patriot Act authorities expire on Friday.

But one possible hurdle to these plans is whether every senator can support the House version, which would only extend the small-business programs for four months. According to a Senate staffer, Senate Small Business Committee Chairwoman Mary LandrieuMary LandrieuMedicaid rollback looms for GOP senators in 2020 Five unanswered questions after Trump's upset victory Pavlich: O’Keefe a true journalist MORE (D-La.) is pushing for at least a six-month extension or more, which could make it hard for the Senate to come to an agreement.


—This story was updated at 10:20 a.m.