52 % of Scots backing the SNP , overall lead over Labour trailing on 24 May . Sturgeon responded by TV debates despite threat of another referendum . Damning survey results on the day it launches its manifesto . TNS surveyed 978 voters aged over 18 across Scotland between March 18 and April 8 .
52 % of Scots backing the SNP , doubling lead over Labour trailing on 24 % . Sturgeon buoyed by TV debates despite threat of another referendum . Damning survey comes on the day Miliband launches Labour manifesto . TNS surveyed 978 adults aged over 18 across Scotland between March 18 and April 8 .