Can Scottish voters influence the outcome of the election?

Scotland's first minister Nicola Sturgeon has said the SNP would be willing to make Ed Miliband prime minister if the Conservatives failed to win an outright majority.

The offer was made during a televised Scottish leaders' debate, and rejected by Labour.

Christian Fraser takes a look at what could happen in Scotland, where he says there does not seem to be a safe seat, following the Scottish referendum in 2014.