If the tax reconciliation bill somehow doesn’t make it to the Senate floor this week, it may have to wait until much closer to Christmas.

Pushing the measure back just a week would not seem to be an option because of December’s other deadline crush: the expiration of the current continuing resolution funding the government through Dec. 8.

That is part of the reason why Republican leaders are so eager to hold a budget reconciliation vote-a-rama and advance the tax plan this week, even as some members question the iteration advanced by the Senate Finance Committee.

The Senate Budget Committee is scheduled to meet Tuesday to package the reconciliation legislation for the floor, a usually perfunctory step. 

Wisconsin GOP Sen. Ron Johnson said Monday he was currently planning to vote “no” on the reconciliation bill at the Budget panel, according to an Associated Press reporter based in Madison, Wisconsin.

“If we develop a fix prior to committee, I’ll probably support it, but if we don’t, I’ll vote against it,” Johnson said, according to the AP.

Budget Chairman Michael B. Enzi said Monday there were no plans to postpone or cancel Tuesday’s reconciliation markup.

Watch: Hatch on Tax Bill Differences With House: ‘We’re Willing to Work Together’

The Wyoming Republican also said the tax bill would not be changed during the markup.

“It won’t be changed in committee. It can’t be changed in committee. Precedent shows the only time there is any change is if the reconciliation has two competing committees with overlapping jurisdictions. There is no overlapping jurisdiction,” he said.

When asked if he was concerned that Johnson may vote against the legislation, Enzi said, “That’s always a possibility.”

Finding solutions

Ohio GOP Sen. Rob Portman, a Finance Committee member and longtime advocate of overhauling the tax code, sought to address Johnson’s concerns that smaller companies were disadvantaged by the Senate tax plan compared to big corporations.

“We were very careful in designing this … to ensure that the smaller companies, which are pass-throughs which pay [taxes] at the individual rate, are also given a substantial tax break to be able to hire more people and invest more in their company,” Portman told the Fox News Channel. 

Another Budget Committee Republican, Bob Corker of Tennessee, said it was “very possible” he could vote against the tax plan at the committee level, noting that his concerns about the fiscal effect of the tax proposal have long been public.

Corker told reporters he has been working with White House officials and GOP tax writers to craft a revenue “trigger” that would kick in if the tax plan does not bring in the desired revenue. 

“You’ve got to have a trigger that, first of all, it’s got to be at a point in time that allows you to recoup what hasn’t been met up until that day,” he said. “So the order of magnitude really depends upon what shortfall might exist.”

Corker said he didn’t want to get into further details “because it just messes everything up,” but he’s been talking to other Senate Republicans who share his concerns.

As for his vote on the Budget panel, the Tennessee senator said, “I’m not threatening anything. I’m just saying that it’s very important for me to know that we’ve got this resolved.”

Republicans have a 12-11 edge on the committee, meaning if Johnson or Corker votes against the plan, the panel would not vote to approve it. 

Alternative route

Even if the Budget Committee voted against send the reconciliation package to the floor, the endeavor would not necessarily be doomed.

Before the Senate adjourned Monday, Senate Majority Leader Mitch McConnell took procedural steps to avoid potential Democratic objections and get the House-passed reconciliation vehicle directly onto the calendar.

It appears the Senate could theoretically vote to proceed to the House-passed bill, with Republicans laying down a substitute amendment that meets the reconciliation instructions based on the marks from Finance and Energy and Natural Resources, without being formally combined by the Budget panel.

Senate Majority Whip John Cornyn said earlier Monday that the plan was to get to the motion to proceed to the tax package Wednesday, setting up Thursday night for the long sequence of amendment votes known as the vote-a-rama.

While there would be time for the whole exercise to extend through the weekend, there’s not much time beyond that.

That’s particularly true if President Donald Trump and leaders on Capitol Hill have not given up hope on an omnibus spending bill to fund the government through next September.

An omnibus would be all but certain to face procedural objections from some corners — whether it be conservatives concerned about excessive domestic spending, defense hawks concerned about too little military spending, or liberals worried about a lack of protections for so-called Dreamers, undocumented immigrants brought illegally to the U.S. as children.

That would mean McConnell would need to have the ducks in a row no later than next Tuesday if there were persistent objections.

“We’re back and we have a lot of work to do before the end of the year and precious little time to do it — funding for the government expires a week from this Friday,” Senate Minority Leader Charles E. Schumer said before he listed a number of other year-end priorities, including the Dreamers issue, the Children’s Health Insurance Program, community health center funding, and cost-sharing reduction payments for insurers on the exchanges.

The top leaders of the two parties in the House and Senate are scheduled to huddle with Trump on Tuesday, after he takes a trip to the Capitol to meet with the Senate Republican Conference.

And the government funding situation is expected to top the agenda at the meeting of Trump and the congressional leaders.

Jennifer Shutt and Ryan McCrimmon contributed to this report.