Comments from establishment Republican leaders, as well as more right-wing elements in Congress, suggest that a GOP-led shutdown fight over immigration could be imminent.

Republicans aren’t eager to suggest that they might threaten to shut down the government again after last year’s disastrous $24 billion fight over the Affordable Care Act and the law’s birth control benefit.

Sen. Mitch McConnell (R-KY), the likely future Senate majority leader, promised outright at his first post-election press conference last week that there would be no government shutdowns or defaults on the national debt.

But McConnell’s promise seems irreconcilable with his resolve, in the same speech, to use the “power of the purse” and the budget process to “push back” against the administration’s “overactive bureaucracy.”

This is the tactic that led to the 2013 shutdown, when Republicans, led by Sen. Ted Cruz (R-TX), wanted to use the budget bill to de-fund or delay the Affordable Care Act.

McConnell’s gentle call for bipartisanship turned threatening when the subject of immigration came up.

He said it would “poison the well” and be tantamount to “waving a red flag in front of a bull” if Obama takes executive action on immigration before the end of the year, as he has promised to do. Democrats maintain the Senate majority until the start of 2015.

McConnell’s office didn’t elaborate to Rewire on what these “red flag” threats might mean in practical terms. “Our members will certainly discuss,” McConnell spokesperson Don Stewart said.

Speaker of the House John Boehner (R-OH) used the same line about how Obama’s executive action could “poison the well.”

McConnell also told TIME magazine, when asked about the pending executive order on immigration, that the way to “push back on executive overreach is through the funding process.”

All of this already signals a willingness on the part of Republican leadership to do the bidding of more radical party members, despite McConnell’s conciliatory rhetoric.

Tea Party favorites Ted Cruz (R-TX) and Mike Lee (R-UT), along with four other Republican senators, signed a letter vowing to use “all procedural means necessary” to block the “constitutional crisis” of the president’s “lawless amnesty.”

And in an op-ed published in Politico Magazine, Sen. Jeff Sessions (R-AL) called on Republicans to thwart Obama’s intentions on immigration reform using the same process that led to last year’s shutdown.

Obama’s “executive amnesty,” Sessions wrote, “cannot be implemented if Congress simply includes routine language on any government funding bill prohibiting the expenditure of funds for this unlawful purpose.” He called this action “ordinary, unexceptional, and used thousands of times.”

Sessions is the ranking member of the Senate Budget Committee and is likely to take over the committee chairmanship when Congress returns next year under Republican leadership.

Most likely, Republicans would attach Cruz’s bill de-funding any expansion of the president’s Deferred Action for Childhood Arrivals (DACA) program as a rider to a budget bill, Brian Phillips, a spokesperson for Sen. Lee, told Rewire.

Phillips, echoing McConnell’s shutdown denials, insisted that using the budget bill to de-fund immigration reform won’t lead to a funding crisis.

“Not every time you cut money forces a shutdown,” Phillips said. “It’s nonsense to talk about it that way.” Phillips added that it’s a “perfectly suitable function of Congress” to hold the administration accountable using the appropriations process.

It is, of course, routine to use a budget document to shape priorities. But using a budget document to directly challenge a signature priority of a sitting president is a bold and rare move that can lead to a government shutdown, as happened in 1995 between President Clinton and the House of Representatives led by Speaker Newt Gingrich, as well as last year.

Using the budget as leverage only works because of the threat of a government shutdown. If the Senate passed a budget bill with policy riders that unraveled one of Obama’s major achievements, his only options would be to pass it and undermine his key policies, or veto it and let the government shut down if the Senate wouldn’t or couldn’t pass a different bill before the funding deadline.

Cruz and Lee, both members of the Senate Judiciary Committee, are trying to make immigration a central issue in the confirmation of Loretta Lynch as the next attorney general. The two issued a joint statement insisting that Lynch should say “whether or not she believes the President’s executive amnesty plans are constitutional and legal.”

It’s clear neither of them believe the action would be legal, even though the details of the plan haven’t been released, the president has never suggested taking executive action that would amount to “amnesty,” and experts say the executive branch is well within its rights to exercise prosecutorial discretion over whom it chooses to deport.

It’s unclear whether there is enough support for immigration reform among congressional Republicans to overcome right-wing opposition, especially after huge 2014 midterm victories convinced many that the GOP don’t need to pass comprehensive reform in order to win.

Pro-reform conservatives are worried, however. As one GOP operative told the Huffington Post, the prospect of Republicans threatening a shutdown over immigration is “like a slow-moving car wreck where we can see exactly where it’s heading.”