I think there is a non-zero chance of the Tories being the surprise story of the campaign. With the SNP almost certain to form the government, and Labour in a state of advanced dissolution, the media is going to be desperate for any sort of narrative to make the campaign interesting. Given Ruth Davidson's personal popularity, and the fact that Labour really serves no purpose(if you want left-wing vote SNP, if you want Unionist you can go Tory, if you want an alternative government your out of luck) I could see a "Scottish Tory Surge" narrative developing with the Tories touching 20%, and perhaps polling marginally above Scottish Labour.
The SNP has also moved visibly to the left in the last few years, something that became evident in the referendum where Westminster SNP areas that had previously been Tory went No. In stealing Scottish Labour's base, its possible the SNP will have alienated a portion(5-7%) of its center-right electorate.
In reality the difference between a 45-22-19 SNP-Tory-Lab and a 45-25-16 result will be marginal in policy terms, but it would be enormous in terms of media narrative.
Perhaps but there is one problem with this theory and it's that we are talking about the Scottish Tories here.
