A potential government shutdown hurtling ever closer, the Democratic-led Senate is ready to approve legislation keeping federal agencies from locking their doors on Tuesday. But disputes with the Republican-run House and among GOP lawmakers themselves ensure that the battle will spill into the weekend at least, and quite possibly beyond.
The result: a high-stakes showdown that is playing out in a climate of chaos, infighting and unpredictability that is extraordinary even by congressional standards.
The Senate planned votes Friday on the measure preventing a shutdown. Senators were expected to pass it after derailing a conservative effort to block the bill and after removing House-approved language that strips money from President Barack Obama's health care law.
That would bounce the legislation back to the House, where GOP leaders already have declared that the pared-down Senate bill was insufficient.
With conservatives insisting that the shutdown bill and a separate debt limit measure present an opportunity to demolish the Affordable Care Act and slash spending, House leaders were not saying what, if any, decisions they had made on strategy.
No votes on the budget bill were expected in the House until at least the weekend. The Senate measure would allow hundreds of thousands of employees at dozens of agencies to continue working, while shielding lawmakers from public scorn.
GOP disunity over what to include in the debt limit measure forced leaders to indefinitely delay that legislation, which is aimed at preventing a damaging, first-ever federal default that the Obama administration has warned could otherwise occur by Oct. 17.
(Read more: Congress reaches new lows in latest budget battle)
At one point Thursday, GOP divisions burst into full view on the Senate floor as a pair of conservatives, Sens. Ted Cruz of Texas and Mike Lee of Utah, forced the Senate to wait until Friday to approve its bill preventing a shutdown.
"The American people are watching this" but expected the vote Friday or Saturday, said Lee, who asked Senate Majority Leader Harry Reid, D-Nev., to not hold the roll call on Thursday.
Reid accused the conservatives of "a big, big stall."
He said he wanted to return the Senate bill to the House as quickly as possible to give GOP leaders there more time to send back an amended bill and avoid a shutdown.
Lee's request also prompted Sen. Bob Corker, R-Tenn., to engage in an icy exchange with Cruz in which Corker accused the two conservatives of seeking a delay because they had emailed their supporters to watch debate on the legislation on Friday.
"My two colleagues, who I respect, have sent out emails around the world and turned this into a show," Corker said, barely masking his disdain. "And that is taking priority over getting legislation back to the House so they can take action before the country's government shuts down."
Just a day earlier, Cruz, a possible 2016 presidential contender, ended a 21-hour speech urging lawmakers to block the Senate bill before Reid amends it to drop the language defunding Obama's 2010 health care law.
(Read more: Cruz ends Obamacare speech after 21 hours)
That talkathon, and Cruz's strategy, has garnered widespread praise from supporters around the country and become a focus of fundraising appeals by conservative groups.
"We are not going to be complicit in giving Harry Reid the ability to fund Obamacare," Cruz said Thursday.
But Cruz and Lee's effort has earned derision from many GOP colleagues, who see it as a ploy that is doomed and increases the odds of legislative delays that threaten a shutdown. Most Republicans want to avoid a shutdown, fearing blame from voters.
Asked Thursday whether he envisions the House approving a simple Senate-passed bill keeping the government open, House Speaker John Boehner, R-Ohio, told reporters, "I don't see that happening." GOP lawmakers said he signaled the same thing at a closed-door meeting Thursday.
They said the House might insert provisions into the shutdown bill repealing an unpopular tax on medical devices that helps pay for Obama's health care overhaul, or erasing federal subsidies for Congress' own health care coverage. They could then dare the Senate to reject the overall measure—and face the fallout from the government shutdown that would result.
But lawmakers and GOP aides cautioned that no decisions had been made, in part because it was unclear whether even those provisions would help win enough votes for House passage.
The debt limit bill was even more complicated and potentially dangerous. Many analysts think even the serious threat of a federal default would jar the economy—for which neither party would relish being blamed.
In an attempt to build support, House GOP leaders considered adding a stack of provisions.
A one-year delay of "Obamacare," expedited congressional work on tax reform and clearing hurdles to the proposed Keystone XL oil pipeline from Canada to Texas were considered certainties. Other possibilities included boosts in Medicare costs for higher earners, land transfers in California and Oregon, and repealing Federal Communications Commission restraints on Internet providers' ability to control available content.
Even so, many conservatives said the debt limit bill lacked sufficient spending cuts.
"It definitely has a lot of goodies in it, things that arguably would grow the economy and arguably would generate more revenue," said Rep. Mo Brooks, R-Ala. "But still you have to address the spending problem."
—By The Associated Press.