The Kantar poll of 18+adults’ Westminster voting intentions, collected between 5th and 9th July 2018, gives the following percentages:

• SNP             39%
• Conservatives 20%
• Labour 19%
• Lib Dems             4%
• Other 5%
• Prefer not to say 14%

This gives SNP support alone equal to the combined Conservative and Labour support.
https://thoughtcontrolscotland.com/2018/07/11/snp-pull-further-ahead-of-tories-and-labour/