Ruth Davidson holds no elected office in the largest part of our country – England, which contains over 85 per cent of the population. She is not a member of Parliament.  She is therefore ineligible to succeed David Cameron as Prime Minister.  But the newly-elected MSP for Edinburgh Central has a good claim today to be the most influential Conservative in the whole country, in the aftermath of the sensational success of the Party she leads in the Scottish Parliamentary elections.  This morning, everyone wants a piece of her – every Tory, anyway.

Coverage of Scottish politics in England is perhaps not as pervasive as in pre-devolution days, and new media means that there is more journalism competing for readers in any event.  A consequence is that even many members of her own party know very little about our fortnightly columnist.  They may therefore be tempted to believe that once of the best-known facts about her – her sexuality – somehow defines her views, attitudes and politics, and that once one knows about this aspect of her life one knows everything else about her, too.

Scotland’s Conservative leader is certainly a moderniser, who pitches her appeal to Scotland’s mainstream mass of moderate voters.  If you want to turn to the dry world of policy for evidence, consider the quiet way in which she has dropped education vouchers.  Support for same sex marriage is considered to be a touchstone for modernisation and she is for it, too.  In an understated and unexcitable way, she is also a Remain supporter.  And some of those who want to return to her own life story will light on the venue of her work as a journalist – the BBC.

So much, so Cameroon – at least, for those who believe that once one knows someone’s views on the EU referendum one knows exactly where to place them on the Party spectrum.  But there are at least three important qualifications to mull.  The first is how she came to lead Scotland’s Conservatives in the first place.  David Cameron won his own leadership election fair and square as the modernising candidate.  Davidson won hers opposing a modernisation proposal which was at the heart of the contest.

Murdo Fraser, her main opponent, argued that the Conservatives should change their name – evidence of how far their political fortunes and self-confidence had fallen as recently as five years ago.  Davidson contested the plan and won the election.  It was a sign of her direction of travel.  She wanted the Tories in Scotland to worry less about themselves and more about the country’s voters, who increasingly yearned for a proper opposition to the SNP – already on its way to the position of dominance which it sealed in last May’s near wipe-out of Labour.

This takes us to a second difference.  The Prime Minister has many political strengths – he is now the Party’s most electorally successful post-war leader other than Margaret Thatcher – but strategic consistency is not among them.  In opposition, he began by presenting himself as the heir to Blair.  In Coalition, he ended up campaigning as the voice of Lynton.  Davidson, by contrast, methodically exploited the failure of Scotland’s other main Unionist party – Labour – and established Scotland’s Conservatives as the main voice of Unionism north of the border instead.

She worked doggedly away at the task before the independence referendum, which opened up an opportunity to project her Unionism more vividly and take it to another level.  This she did with verve and passion, taking the fight to Nicola Sturgeon – yes, that’s the same Nicola Sturgeon who performed so powerfully in the general election TV debates last year.  Davidson didn’t fight a Westminster seat last May, but her performance the autumn before will have been a factor in the Party holding its ground in Parliamentary terms.

What the Scottish Conservatives have now done is what some hoped they would do last year – that’s to say, break out from that miserable ground (a solitary Westminster seat held by a whisker) to reclaim some of the territory which the SNP and Labour swiped from it during the last 30 years or so – in the borders, in parts of Aberdeenshire, in Eastwood near Glasgow.  The Tory vote was also well up elsewhere, which boosted its top-up MSPs – two are from Glasgow, for example.  Three-quarters of the Party’s MSPs are brand-new.

Davidson’s campaigning strengths take us to a third difference which, in a cautious way, she has alluded to herself on this very site.  In a joint article with her friend Stephen Crabb, she wrote about her upbringing “in houses where nothing came for free” and lauded what the Conservatives did for John Major – the “boy from Brixton”.  The positioning was careful but clear – and uncomfortable for a Party leadership headed by an Old Etonian whose comfortable upbringing is exploited by its political opponents.

The authors lauded a “muscular” One Nation conservatism.  This combination of heart and head – and body strength too, evidently – is very Davidson.  Indeed, the more one thinks about it, the more one grasps that she is weaving the different strands of modern conservatism together successfully.  The former BBC journalist also served in the territorial army.  The openly gay politician is also a practising Christian politician.  There is no contradiction whatsoever in that combination in the eyes of very many of her co-believers, not to mention a big majority of non-believers as well.

It is a statement of the geographical obvious that London is not Scotland – and the culturally obvious, too.  None the less, there is a lesson to be drawn from Davidson’s success and Zac’s failure on Thursday.  He was absolutely right to ask Sadiq Khan some searching questions about his record on extremism.  This site will never say otherwise.  The mistake wasn’t that his campaign did so.  It was rather that, by the end of the contest, it seemed to be doing little else.  What was coming through to voters was a negative message about Khan, not a positive one about Goldsmith itself.

Davidson is emphatically positive rather than negative – for strong defence, for lower taxes and, above all, for the Union.  She is for things rather than against things.  So is Zac – but the more the campaign went on, the less this was communicated.  One of his party allies is savage about Lynton Crosby’s role in what happened on Thursday precisely because it was a non-role – arguing that, since Crosby Textor Fullbrook took the campaign on, Crosby should not, in this source’s words, “have ducked out from the start because he thought Zac would lose”.

Some will claim that the Conservatives are still a minority cause in Scotland, that Davidson has simply been handed an electoral windfall by Labour’s collapse, and that her cause is over-hyped. And that London, post-Boris, was Labour’s to lose.  It is true that politicians can be pushed up only to be pulled down.  One need to look no further than Sajid Javid for an example – though it is also true that those pulled down are sometimes pushed up again.  But there is reason to believe that Davidson’s kind of One Nation conservatism is the best hope for the Party’s future.

The old truths apply.  At the last election, the Conservatives won 37 per cent of the vote.  For 2020, we should aim to gain over 40 per cent.  This site has always argued that without a social justice appeal – pitched at delivering more homes, jobs and savings to younger voters especially – this simply won’t happen: that’s why we produced the ConservativeHome Manifesto.  There is more to British politics than the EU referendum, vital though it is.  After it ends and the smoke clears, the Party will need Davidson’s sense, guts – and, yes, positivity.