(CNN) It's a congressional version of hot potato that will determine if a government shutdown begins as soon as Tuesday.
The Democratic-led Senate moved quickly Friday to pass its preferred short-term spending plan to keep the government funded beyond the end of the current fiscal year on Monday, tossing it back to the Republican-led House.
This sets up a weekend showdown between Republican House Speaker John Boehner and tea party conservatives in his GOP caucus, which demands that any spending measure must eliminate all money for Obamacare.
The Senate began Friday by voting to overcome a filibuster led by GOP Sen. Ted Cruz of Texas against the spending plan, clearing the way for another vote in which Democrats restored funding for Obamacare in the plan.
It then approved the revised spending measure -- called a continuing resolution -- through mid-November, 54 to 44.
Cruz waged a 21-hour floor speech this week against Obamacare, but more moderate Republicans rejected his tactics in voting with Democrats to move ahead on the measure.
Boehner indicated Thursday the House could revise the Senate's version and send that back, a move that Senate Majority Leader Harry Reid warned would result in at least the start of a government shutdown next week because of the time it would take the Senate to reconsider the measure.
Cruz, who became the face of the tea party push to defund Obamacare, said Friday he expected his GOP colleagues in the House to continue the fight by revising the spending plan, which would mean "this issue is coming back to the Senate."