This is the story of the most marginal constituencies. There is not official definition of a marginal. Many people place it at a 5000 vote difference between first and second place, or less. There have been 32 constituencies where the winner won by 30 votes or less. In 1997 Mark Oaten, Liberal Democrat beat his Conservative rival by just 2 votes. The election was marked by controversy as another candidate ran under the banner “liberal democrat top choice for Parliament”. This guy, Richard Huggard had also ran as a candidate in a European election back in ’94 as a literal democrat (no typo), garnering over 10000 votes. This practice of choosing a similar or confusing name was outlawed a few years later.
There are 146 marginal constituencies this election with the most marginal being Gower. A switch of 27 votes would swing the election from Conservative to Labour. That is of course assuming the same people voted in the same way. We know this doesn’t happen and this phenomenon is called churn.
Have you ever wondered what happens if there is a dead heat? Firstly there will be a recount. Then probably another one. If there is still an equal number of votes between first and second then it is up to the acting returning officer to decide how the winner is chosen. A coin toss is one suggested method.
In the 1886 election, there was a tie between John Edmund Wentworth Addison MP and the Liberal candidate. The rules at the time stated that the presiding officer had a casting vote, and this was given in due course to the incumbent. Addison was reelected.