Polling shows Scottish National Party has extended its lead over Labour . The latest poll by Survation for the Sunday Herald puts support for the SNP at 38 per cent and Labour on 30 per cent. Jim Murphy , its Scottish leader , among those on course to lose their seats .
Polling shows Scottish National Party has extended its lead over Labour . Constituency surveys suggest Labour party faces unprecedented wipeout . Jim Murphy , its Scottish leader , among those on course to lose their seats .