The SNP is facing the prospect of a by-election in Edinburgh West. If you could pick a seat where the Lib Dems would be well placed to win a by-election, they don't come better than Edinburgh West. With Labour and Conservatives having no chance of winning, there vote could be squeezed, the new Corbyn Labour party might win back some votes from the SNP, and the Lib Dems just 3210 votes behind in 2015 could win.
2015 Result:Conservative: 6732 (12.3%)
Labour: 6425 (11.7%)
Lib Dem: 18168 (33.1%)
SNP: 21378 (39%)
Green: 1140 (2.1%)
UKIP: 1015 (1.9%)
MAJORITY: 3210 (5.9%
Before getting too excited though, the Lib Dems have to remember that their membership in Scotland is pathetic and they will be easily overwhelmed by SNP activist and money.
The SNP have risen further in the polls since the general election, and if the have sense, they will call the by-election as soon as possible. Better to accept their MP has done wrong and choose someone else than hang on until it starts to irritate people into not voting or switching to other parties.
One of the features of Nick Cleggs leadership was the Lib Dems awful performance in by-elections. The stakes for the Lib Dems are high, if there is a by-election and the Lib Dems don't improve on 2015, then it is another nail in the coffin.