WASHINGTON — The Senate will conclude one of its more unpredictable — and stranger — weeks on Friday when it is expected to approve a bill to finance the federal government, including the health care law that Republicans have been trying to kill.
Barring any unforeseen twists, which can never be ruled out on Capitol Hill, the Senate will proceed to a series of votes at 12:30 p.m. that will send a budget bill to the House that Republicans there have vowed to change because of their strong opposition to any measure that helps the administration put the health care law into effect.
That will set up a game of legislative Ping-Pong that will tip the government perilously close to shutting down on Tuesday.
Senator Harry Reid, the majority leader, has said he would reject anything but a plain budget bill, including Republican suggestions to delay the health care law or to repeal a tax on medical devices that would help pay for it.
But House Republicans and Speaker John A. Boehner seem intent on not surrendering the budget fight without wresting concessions from the Democratic-controlled Senate and President Obama.
It is unclear what the Republicans want, other than a complete repeal of the health law. Senior House Republicans continue to assess their options as the Senate prepares to vote on Friday, and are likely to insert any changes over the weekend, when the House plans to be in session.
One idea, according to a Republican who had spoken to the leadership, would be to put an amendment in the Senate budget bill that would eliminate health insurance subsidies for members of Congress and many of their aides, who must purchase their insurance on the exchanges that are part of the new law.
“That is an arrow in the quiver,” the Republican said.
That strategy, Republicans said, would put Senate Democrats in the uncomfortable position of either approving the amendment or rejecting it and risk appearing that they are willing to shut down the government over subsidies to themselves and their staffs.
But the Senate would not be able to act on any House bill until Monday, the day before the government is set to shut down if an agreement is not reached.
Getting to that point could be bumpy, starting with the Senate debate on Friday.
Conservative Republicans like Ted Cruz of Texas and Mike Lee of Utah caused a stir on the Senate floor on Thursday when they raised objections that forced a budget vote, which could have occurred that afternoon, to be pushed back until Friday.
Mr. Cruz’s 21-hour speech from Tuesday afternoon until noon Wednesday was a sensation in the conservative media and among Tea Party activists, even as some Republican colleagues accused him of putting his own ambitions and a desire for national attention above the party’s interests.
He and his allies in the Senate, like Mr. Lee, have planned a sequel of sorts on Friday with a series of interviews on conservative radio shows and on Fox News.
On Sean Hannity’s Fox News program on Thursday night, Mr. Cruz encouraged viewers to go to a Web site that lists the telephone numbers of Republican senators who are opposed to his plan, and he encouraged them to keep fighting as Friday’s vote neared. He offered some dismissive words for his Republican colleagues.
“They’re beaten down, and they’re scared that if we stand together on this, and if a government shutdown results, that Republicans will be blamed and it’s too politically risky,” Mr. Cruz said, adding: “I hope they have second thoughts. I hope they listen to their constituents.”
The campaign has infuriated many of his fellow Republicans, who have done little to conceal their outrage. They have accused Mr. Cruz and his supporters of staging self-serving publicity stunts fueled by social media-savvy outside groups that have urged their followers to bombard the Senate with phone calls.
Mr. Cruz and his allies “have sent e-mails around the world and turned this into a show,” Senator Bob Corker, Republican of Tennessee, said on Friday. “And that is taking priority over getting legislation into the House.”