What is Ruth Davidson to do about her Boris Johnson problem? The view from north of the Border is that unless he blows himself up — far from unthinkable, admittedly — it looks increasingly like the former foreign secretary will be the next prime minister. He is far ahead among Conservative MPs, and also among the Tory party members who will ultimately choose between the final two candidates.

Davidson and Johnson have previous. She has long been unappreciative of his constant pursuit of personal advancement over party loyalty, and was especially contemptuous of his last-minute decision to support Brexit, leaving David Cameron high and dry. The pair may share some liberal sensibilities — depending on which Johnson gets out of bed that day — but there is little love lost.

But this is politics, and in politics you don’t have to get along. You have to cut deals, agree positions and use what leverage you have. If it is to be Johnson, then Davidson has no choice but to find a way of co-existing. Johnson, who until the next general election at least would be reliant on the parliamentary votes of the 13 Scottish Conservative MPs, a number of whom are loyal to Davidson, will also have to play along.

There is a view in Scotland, as I outlined here a few weeks ago and as was more robustly stated by commentator Kenny Farquharson in the Times this week, that Johnson’s ascendancy would be a disaster for Davidson’s Scottish detoxification project.

Some believe the very act of seeking accommodation will expose her as a hypocrite, given her previous animus, and will hand a whole new armoury to the SNP ahead of the 2021 devolved election, where Davidson is expected to be the main challenger to First Minister Nicola Sturgeon.

This may prove to be true. But leading Scottish Tories argue a different outcome is also possible. “It’s not as if Ruth’s going to be on his campaign team and is hardly likely to endorse him,” one party source said. “What she’s said is that she has worked with him before, when he was foreign secretary, and that she will work with whoever becomes prime minister. That’s just a statement of fact. I mean, that also applies to Nicola Sturgeon, right?”

Party insiders say they have stood up to the Conservative government at Westminster when they have seen it as being in Scotland’s interests, and will continue to do so, pointing to the issue of immigration, where Scottish Tory attitudes are often considerably more liberal. They will seek “a pragmatic, balanced approach that’s firm when necessary but doesn’t turn everything into a political game”. “We think that’s where most voters are,” adds a source.

Much will depend on how Johnson behaves, of course. The opportunist who wrote two different columns backing and opposing Brexit the day before announcing his decision will inevitably be unpredictable. But the view that he will automatically be disliked by most Scots is dismissed as “lazy – it’s more complex than that.”

What Johnson or any successful candidate will have to do, says a Scottish Tory insider, is “start understanding the reality of the modern UK. This is not a centralised country any more – we have these massive new power centres. They have to understand the new Union better if we are to see off the threat of separation.”

Among the proposals being pushed by Davidson, and supported by a number of the candidates, is for the creation of a new Union Unit in No 10, to take account of how future policy and action impacts across the entire country.

This desire for a prime minister with broad national sympathy is perhaps reflected in the breakdown of where Scottish Tory MPs are placing their first-round votes. Four are backing Michael Gove — a Scot — while two are supporting Matt Hancock and one Jeremy Hunt. Johnson may only be able to count on the vote of his occasional henchman Ross Thomson. Murdo Fraser, the Tories’ influential shadow finance spokesman at Holyrood, wrote in support this week of Rory Stewart. Davidson, in her new weekly Mail on Sunday column, also spoke warmly about Stewart, even if he is given little chance of winning.

While admitting the constant disruption at Westminster is not ideal for a party facing a devolved election in less than two years, the Scottish Conservatives nevertheless remain bullish. They point out that while the whole UK party was hit hard in the recent EU elections, Scotland saw the highest Tory vote share in any region (11.6 per cent). The Scottish party also, uniquely, emerged from the election with the same number of MEPs it entered with (one, but still).

One source points out that the Scottish electorate, which deals with a number of different democratic institutions and different electoral systems, has become rather sophisticated in its thinking in each separate scenario. “We have a distinct political landscape in Scotland and the Scottish Conservatives have a distinctive offer. Our core message going into 2021 will be that if people have had enough of constitutional arguments and don’t want another independence referendum, if they want to get on and focus on other matters, vote for us.”

While Davidson wouldn’t choose Boris Johnson as PM — and she is likely to indicate her support for a candidate at some point in the next few weeks — she believes she can make it work. But, of course, she has to believe that.