Of all the words spoken and written about politics in the UK last week, perhaps the most revealing were delivered in a thick Glasgow accent on a mid-morning radio call-in show. “See that Ruth Davidson; she’s the People’s Tory.” The gentleman caller had palpably been impressed by the performance of the Scottish Conservatives leader during the big EU debate at Wembley the previous night.

Davidson was the star turn in the three-strong Remain team and, on several occasions, made Boris Johnson, a man whose views she is known to despise, look like a second-rate student union bawler. If Johnson is seriously considering becoming David Cameron’s successor, he had better start improving his oratory as he may have to grow accustomed to crossing swords with the formidable Ms Davidson in the very near future.

What happened on Thursday night and into the early hours of Friday morning was nothing less than a hard-right coup d’état. Davidson has previously sidestepped any suggestions that she might ever want to seek high office at Westminster, but the nature of Cameron’s humiliating defenestration may force her to reconsider… even if only to thwart Johnson.

His political achievements are like the Mayor of Trumpton’s compared with Davidson’s. Very little that he has ever achieved in his political and professional career has not been aided by the influence and opportunity that only money can buy in parts of England. Davidson, on the other hand, has gained her political success in the most inhospitable terrain that a Tory can ever encounter: working-class Glasgow.

The first signs that she was beginning to achieve that which was once deemed to be impossible – detoxifying the Tory brand in Scotland – were evident on the doorsteps of Glasgow during last year’s Westminster election campaign. The up-and-coming young chairman of the Glasgow Conservative Association, Kyle Thornton, spoke last year of the Ruth Davidson effect unfolding before him. “Whereas previously, many people in certain neighbourhoods would never give you the time of day, now they are happy to chat. And though they may have no intention of giving you her vote, they always say that they admire ‘that Ruth Davidson’.”

The former UK Olympic middle-distance runner Brian Whittle is now a Tory MSP, having squeezed in on the list on the back of the party’s mini-revival. He does not come from traditional Tory stock. He told me: “Ruth Davidson was the main reason I decided to get involved in politics and stand as a Tory. She is an inspiration.”

These voices, like the one that spoke so admiringly of her on the phone-in, are the voices of ordinary, middle-class Scotland who had turned their backs on the Tories in the wake of Thatcherism and the poll tax. For the first time in a generation, they are finding that it is safe to enter hard neighbourhoods with a blue rosette. The Tories, having been detoxified, then marched on Holyrood, replacing Labour as the official opposition. This would have been deemed impossible just a year ago and much of it is down to the political pocket battleship that is Ruth Davidson.

English pro-Europe Tories who have come to loathe Johnson and Gove may regard Davidson as a potential champion

Events of the past few days, though, have come together to see her emerge as one of the most important politicians in the UK. Cameron had already spotted her potential as a player during visits north to Scottish party conferences. Thus, she was already developing a solid reputation in the UK party. Her Wembley performance, though, brought her to UK-wide attention.

Susie Boniface in the Guardian wrote: “It is no surprise to anyone who has watched Davidson since the Scottish referendum that she is an impressive politician. Unlike so many of those we’re disdainful of in Westminster, she gives every impression of being a normal, rounded human being.”

English pro-Europe Tories who have come to loathe Johnson and his wingman, Michael Gove, for their unpleasant campaign to unseat Cameron may regard Davidson as a potential champion. She is only just getting into her stride as opposition leader at Holyrood, but has already begun to make life tough for Nicola Sturgeon on health and education, something that Scotland’s first minister has rarely encountered during her gilded political career.

Following Sturgeon’s declaration of intent on Friday morning about a second independence referendum, it seems as though Davidson has emerged at just the right time for Scottish unionists. The first minister would be heading into this referendum possessing a moral mandate that eclipsed Alex Salmond’s political one in 2014. She will expect to win former No voters who share her disgust that Scotland is being frogmarched out of Europe by a gang of the Scarecrow Right. The responsibility for creating a pro-unionist narrative to oppose this will fall to Davidson.

The Tory leader is blessed with a pleasing delivery, clear in tone and pitch, which suggests a sound education rather than a privileged one. The easy barbs and jibes that come readily when Johnson, Cameron or Osborne are the intended targets do not really work with Davidson. She has lived most of her adult life in Glasgow and chose the Glasgow North-East constituency as the venue for her first two political campaigns.

In Holyrood the previous week, Davidson was calling on Sturgeon to account for another set of dismal education figures that indicated a widening attainment gap between the haves and the have-nots. If you didn’t know she was the leader of the Scottish Conservative and Unionist party she could have passed for a soft-left European Christian Democrat. Sturgeon wastes few opportunities to exhibit her contempt and disdain for Tories and occasionally seems to spit the word “Tory” out as if she were chewing a wasp. But she has respect for Davidson, whom she deems her intellectual equal and a worthy opponent.

Over the course of the next few years, Ruth Davidson will become the biggest obstacle to her dream of an independent Scotland.