The one sign Peter Dutton’s campaign to become Prime Minister was doomed

The mistake Peter Dutton (pictured) made the night before the leadership vote is revealed

The critical mistake that Peter Dutton made before the leadership vote has been revealed.

Mr Dutton appears to have been so sure he would win the Liberal leadership spill that he went out for a ‘celebratory’  dinner – only to then lose to Scott Morrison.

While Mr Dutton was out eating with ally Mathias Cormann, Mr Morrison was sitting in his office at Parliament House making calls as he tried to gain as much support as possible from his colleagues.

Labor campaign strategist and commentator Dee Madigan told news.com.au that the ‘mood’ of the rebel camp’s dinner was ‘celebratory’, as though the vote had already gone in Mr Dutton’s favour. 

‘Dutton out to dinner instead of making phone calls was such a surprise to me,’ Ms Madigan said.  

It followed the decision by former Prime Minister Malcolm Turnbull to delay the party room meeting until Friday at midday – a move that allowed Mr Morrison to garner his votes.

It seems that the expectant Prime Minister-to-be Peter Dutton (right) was out celebrating his win with his supporters (Mathias Cormann pictured left, was at the dinner) before it had even happened

It seems that the expectant Prime Minister-to-be Peter Dutton (right) was out celebrating his win with his supporters (Mathias Cormann pictured left, was at the dinner) before it had even happened

Ms Madigan said that this was the most important decision made throughout the entire chaotic week.

‘It gave Scott Morrison time to do the numbers, which is what Turnbull would’ve wanted. It was the only sound thing to happen,’ she said. 

When the rebel camp went into the party room meeting on Friday, they expected to exit with Mr Dutton as Australia’s next Prime Minister.

The history books will show the former home affairs minister made a grave miscalculation, as Mr Morrison swept up 45 votes compared to Mr Dutton’s 40.

After a week-long saga that saw Mr Dutton attempt to rid Mr Turnbull of his leadership position, both he and his supporters were confident they held the majority to push him into the top spot.

However, when the three-way vote between Mr Dutton, Mr Morrison and Minister for Foreign Affairs Julie Bishop came to fruition, the rebel camp discovered some of their supporters had changed their minds over the risk of another High Court scandal. 

On Thursday night, Mr Dutton and his supporters scrambled to obtain 40 of the 43 signatures Mr Turnbull demanded in order for the party room meeting to go ahead. 

With just three votes left, Mr Dutton and his team were confident they would be able to acquire them the following morning.

The history books will show the former home affairs minister made a grave miscalculation, as Scott Morrison (pictured, middle) swept up 45 votes compared to Mr Dutton's 40

The history books will show the former home affairs minister made a grave miscalculation, as Scott Morrison (pictured, middle) swept up 45 votes compared to Mr Dutton’s 40

Yet, the camp came to a standstill on Friday morning when Solicitor-General Stephen Donaghue QC informed Mr Dutton that there was a ‘risk’ to his eligibility.

It was believed that Mr Dutton may have been seen as ‘ineligible’ by the High Court under section 44 of the Constitution, as his family trust owns two childcare centres in Brisbane.

Concerns were raised among the MPs who pledged their support for Mr Dutton, as they didn’t want to face the risk of another High Court crisis.

This saw some of them sway their allegiance and vote for Scott Morrison, Australia’s next – and 30th – Prime Minister.

The result came as an embarrassment to Mr Dutton, who had been just a few votes a away from defeating Mr Turnbull in a spill just days earlier. 

Read more at DailyMail.co.uk