The YouGov survey for The Times puts the SNP on 42% (+1 from last month), the Tories on 29% (+1) and Labour on 19% (+1).
The Liberal Democrats are down one point to 6%, as are the Greens and Ukip to 2% and 1% respectively.
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According to the Scotland Votes website, the vote shares could see the nationalists claim 47 seats on June 8, followed by the Tories on eight, the Lib Dems on three and Labour on one.
Scottish Labour leader Kezia Dugdale also enjoyed a small boost of four points to bring her positive rating to 26%.
The poll found support for independence was unchanged from the 2014 referendum, at 45% Yes and 55% No.
In a slight shift from the EU referendum result in Scotland, in which 62% voted remain and 38% opted to leave, 57% said they now think Brexit is wrong while 37% said they believed it was right.
YouGov surveyed 1,032 between May 16 and 18.