Once they have peaked they have only one direction they are going to go

One of the consolations of the SNP surge in Scotland is that once they have peaked they have only one direction they are going to go.

Down.

And once they start slipping down all sorts of boots will be giving them a kick.

http://www.theguardian.com/politics/2015/may/04/nicola-sturgeon-questions-legitimacy-of-uk-government-without-scottish-mps