Liz Leffman winning, obviously. There’s also plenty of scope short of winning for the Witney by-election to count as an excellent result for the Liberal Democrats, so how to judge the result when it comes through?
One factor to bear in mind is just how poor Liberal Democrat results in Parliamentary by-elections have been for a long period of time. A mere 1.9% increase in the Lib Dem vote would be the biggest increase in the Lib Dem vote in Parliamentary by-elections since July 2007. Way back then on the same day the Lib Dems got an 8% increase in Sedgefield and a 3.3% increase in Ealing Southall. Since then the party’s best vote increase was just 1.8% in Henley (2008).
In fact, since the 2005 general election there have only been two by-elections in which the Liberal Democrats scored a greater than 10% increase in the vote. Both of those were in 2006: the win in Dunfermline and West Fife and the near miss in Bromley.
All of which rather puts into context the Liberal Democrats starting this contest on 6.8% of the vote.
Here, then, are the key things to look for on share of the vote and change in the vote. Take a look down the left hand column to see what various vote shares might be secured by Liz Leffman and then read across to see what they would mean even if the result is short of victory:
|If Liz Leffman’s vote share is…||then vote share will be…||… which makes it highest vote share in a Tory-held seat since…||… and vote increase will be biggest rise in Lib Dem vote in a Parliamentary by-election since…||… which makes it best vote share change in a Tory-held seat since…|
|5.0%||June 2008 (Henley)|
|6.9%||An improvement on 2015|
|8.5%||June 2008 (Henley)|
|8.7%||July 2007 (Ealing Southall)||June 2006 (Bromley & Chislehurst)|
|14.9%||June 2006 (Bromley & Chislehurst)|
|19.5%||An improvement on both 2010 and 2015|
|23.1%||Best Lib Dem result in the seat this century|
|24.5%||September 2004 (Hartlepool)||May 2000 (Romsey)|
|26.1%||July 2004 (Birmingham Hodge Hill)|
|27.9%||June 2006 (Bromley & Chislehurst)|
|28.1%||July 1993 (Christchurch)|
|30.9%||Best ever Lib Dem result in the seat|
|33.0%||September 2003 (Brent East)|
|35.4%||July 1993 (Christchurch)|
|38.0%||May 2000 (Romsey)|
It’s also worth adding that if the Liberal Democrats finish second, this would be the first time the party has done this in a Parliamentary by-election save for Eastleigh (where the party started and finished in first place) since November 2012 (Manchester Central).
If Liz Leffman wins it’ll be the first time the party has gained a seat in a Parliamentary by-election since Dunfermline and West Fife in 2006.
In the meantime, you can help Liz Leffman achieve one of those historic outcomes here.