The Senate is poised to pass a stopgap spending measure today, and send it back to the House, with just four days to go before a threatened federal government shutdown on Tuesday, October 1.  Today’s Senate votes will begin a weekend of negotiating and brinkmanship that could continue until spending authority expires late Monday, September 30.

The Senate is scheduled to act today by holding a series of votes beginning midday to end formal debate on the budget bill, which will keep the government operating through November 15.  Using Senate rules permitting him to change the wording of a spending measure approved by the House last week, Majority Leader Harry Reid (D-NV) is expected to strip out language that would defund the Affordable Care Act, change the expiration date of the funding bill to November 15, and pass the measure with a simple majority achieved entirely with Democratic votes.

If the current plan holds, Senate Democrats will vote to amend the bill  and send it back to the House.  Senate Majority Leader Reid launched the Senate proceedings today by making no formal statements. The House on September 20 passed a short-term spending plan that  continued to fund government operations through December 15 but withheld funding for Obamacare.

The Senate votes today will test the clout of Republican Ted Cruz (R-TX), who is working to prevent Democrats from cutting off debate and stripping out the House language that defunds Obamacare. The calendar gives lawmakers few options, particularly in the Senate, where a single member can force as many as four days of debate on a bill.  One option for Senate Democrats would be to leave Washington once their version of the bill is passed and refuse any changes. Such a move would put all the pressure on the House to accept the Senate’s version of the measure or risk a government shutdown.

The fate of the bill remains in limbo in the House  and GOP leaders are expected to use a series of votes today to once again gauge the mood of their rank-and-file before determining how to proceed.   Some House Republicans have vowed to reject the restoration of the funding for the health-care law, and may opt to send the bill back to the Senate again with more changes.   Senate Majority Leader Reid has said he would reject anything but a “clean” budget bill, including House Republican suggestions to include a measure with a one-year delay in the mandate that uninsured individuals purchase health insurance.  Senate Democrats has said they would reject that idea and that such a strategy would just invite a shutdown.

House Speaker John A. Boehner (R-OH) and his leadership team urged conservative members yesterday to shift their focus on the health-care law to the coming fight over the federal debt limit.  This strategy would allow lawmakers in the meantime to try to reach an agreement on a plan to fund federal agencies into the new fiscal year.  However, some House Republicans objected to Boehner’s tactic of holding a quick vote on his debt-limit plan, instead preferring to fight longer on the spending bill.

Late yesterday afternoon, Boehner and his leadership team convened an emergency meeting to try to formulate a solution.  They emerged with no answers and no clear path forward for any piece of legislation to keep the government open or to make sure the Treasury Department can continue to pay the country’s bills by raising the debt ceiling.

The Treasury Department said this week that the nation is likely to exceed  its borrowing authority on October 17.  Concerns that the budget impasse will hurt economic growth helped send the Standard & Poor’s 500 index to its first weekly decline since August.  A prolonged shutdown could reduce fourth-quarter economic growth by as much as 1.4 percentage points, depending on its length, economists said this week.