BORIS Johnson has embraced a harder Brexit this week to get over his personal issues and fight off Jeremy Hunt, allies and rivals believe.
The frontrunner for No10 will be kept in line by Brexiteer veteran Iain Duncan Smith, his new campaign chair, according to supporters.
It comes after BoJo spent weeks trying to please both sides on Brexit to build support among MPs.
He won the votes of Tories across the spectrum, from Remainer Matt Hancock to arch-Eurosceptic John Redwood.
Mr Johnson was accused of saying different things to different groups, telling Brexiteers he'll go for No Deal while reassuring centrists he wants a more moderate path.
But in recent days he has taken a tougher line, vowing to quit the EU on October 31 "do or die".
Brexiteers have praised the influence of campaign chair Mr Duncan Smith, dubbed "The General" thanks to his military background.
Boris agreed that we would leave the EU at Halloween come hell or high water
Mark Francois
Mark Francois, vice-chair of the hardline European Research Group, told The Sun: "When we met with Boris prior to the first ballot, he agreed that we would leave the European Union at Halloween come hell or high water.
"So his remarks in the last few days are entirely consistent with what he told us.
"The added advantage of having IDS chair the campaign is that not only has he fought a leadership campaign before, but his military background will add some drive and vigour to the collective effort."
Brexiteer Andrew Bridgen said BoJo's recent rhetoric "puts clear blue water between him and Hunt".
And Steve Baker added: "Boris is doing everything I expected. He's going to be a great PM."
BOJO 'WOBBLE'
One MP said that BoJo had been subject to a "battle for the emperor's ear" thanks to his status as clear frontrunner, with various figures competing to wield maximum influence over him.
Remainers who back Boris are now worried that the Brexiteers have the upper hand and admit that No Deal has become more likely.
A Hunt campaign source accused Mr Johnson of veering to the right to distract attention from police being called to a row between him and his girlfriend.
The source told The Sun: "If you're having a wobble tack to the right, is always a sage bet in the Tory party."
A source close to Boris admitted that he was taking a tougher line to appeal to party activists who are overwhelmingly pro-Brexit.
They said: "In the first part we were trying to appeal to MPs by building the broadest base of support possible.
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"For the second round, it's all about speaking to the members - and they want us out on October 31 come what may."
The first half of the Johnson campaign was run by influential MPs such as Grant Shapps and Gavin Williamson.
But the second round is being overseen by experienced behind-the-scenes operators who have previously run national election campaigns.
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