LONDON — Britain’s zombie prime minister refuses to die.

After two years in which she ducked articulating a clear Brexit position, Theresa May has finally made her move. Despite being rocked by twin resignations of two of the biggest beasts in her Cabinet on Monday, the prime minister refused to yield, daring her own party to drag her from the soft Brexit course she has now set.

The initial signs suggest May's obstinance may just succeed — or at least enable her to fight on a bit longer. Despite all the noise, the arithmetic in parliament has not changed. For now, hard-line Brexiteers do not have the numbers to remove May from power and cannot force their preferred version of Brexit through the House of Commons.

In a week when she faces two excursions onto the world stage, as she heads to Brussels for a NATO summit Wednesday and then returns home to welcome U.S. President Donald Trump on his first official visit to the U.K., May will need to draw further on her reserves of obstinance.

Barely half an hour after No. 10 revealed Boris Johnson's resignation on Monday afternoon, May was on her feet in the House of Commons vowing to push ahead with the government’s new Brexit plan in spite of the rolling chaos threatening to engulf her government. Later, amid rumors of an imminent leadership challenge, May was cheered by Conservative MPs as she addressed a behind-closed-doors meeting of her parliamentary party.

Labour aides now openly talk of a new “coalition of chaos” to bring down the government when the final agreement is brought back to the Commons.

Throughout, May insisted her latest Brexit offer, agreed Friday with her Cabinet at her country retreat Chequers, which would see the U.K. permanently aligned to EU rules on goods and agriculture, would be published in full on Thursday as planned — just as Trump arrives for dinner at Winston Churchill's ancestral home, Blenheim Palace.

True to her mantra of “getting on with the job,” May rounded off a day of high drama by replacing the firebrand Johnson as foreign secretary with Jeremy Hunt, a minister who has held the notoriously challenging health portfolio in government longer than anyone else in modern U.K. history. Out goes showmanship, drama and danger, in comes a steady hand and cool head.

Kicking cans down the road

But pull the camera back a little further and the picture is less rosy for the prime minister. She may have the numbers to cling to power, but it remains unclear whether there are enough MPs prepared to back the Brexit she is pursuing in order for her to see it through.

Labour aides now openly talk of a new “coalition of chaos” to bring down the government when the final agreement is brought back to the Commons, by voting with hard-line Conservative rebels like Jacob Rees-Mogg, leader of the pro-Brexit caucus in the Commons, and the Scottish National Party against any proposed deal the government strikes with Brussels along the lines of May's plan.

Rees-Mogg and others, however, now fear a coalition of Tory Remainers and Labour MPs voting through a soft Brexit over the heads of hard-line Brexiteers in the Conservative Party.

“If the government plans to get the Chequers deal through on the back of Labour Party votes that would be the most divisive thing it could do," Rees-Mogg told journalists after listening to May's address to MPs. "It would be a split coming from the top, not from the members of the Conservative Party across the country,”

What is more, it remains unclear if the deal the U.K. prime minister is expending so much political capital pursuing stands any chance of being accepted in Brussels.

“Go back to basics,” said one leading U.K. aide who has been intimately involved in the Brexit talks. “She has handled these negotiations in about as catastrophic a way as is imaginable. She failed to prepare for no deal and she allowed the entire thing to be pushed through the prism of Northern Ireland. What are you left with? We’re going to offer vassal state with a note attached saying ‘would you like your £39 billion by check or direct debit?' It is catastrophic and she is to blame.”

May herself conceded to MPs that unless the EU changes its negotiating position, "there is serious risk it could lead to no deal.” She said this would be a “disorderly no deal” as well because neither side would be able to countenance signing a withdrawal treaty under this scenario.

Despite the chaos in the British Cabinet Monday, Brussels showed no sign of changing tack.

May limps on

As MPs piled into parliament's bars and restaurants at the end of the day, there was one silver lining for May's team — the last vestiges of ambiguity that have hung over the Brexit process finally appear to have burned away, leaving the stark reality of the situation clear for all to see.

The prime minister now appears ready to face down a leadership challenge from the party’s hard-line Brexiteers in order to push ahead with her plan. A spokesman for May told journalists that the PM is prepared to fight and win a vote of no confidence if necessary.

Conor Burns, Johnson’s former parliamentary aide, said there is “no sense of a vote of confidence” among his party. “The interest is to change the policy, not the prime minister,” he said. Another Tory MP, a former Cabinet minister speaking on condition of anonymity, said the prime minister is safe: “Clearly she is not going anywhere and there is no mood to do that either.”

But if the EU's red lines do not change, May will be back facing another crisis by the end of the year. Only this time, she may not be able to survive.