By-elections might not be able to change the Government, but shock results can change politics and change Britain.
And now we have a chance to do just that in Lewisham East.
Since the referendum, every time Jeremy Corbyn could have stood up to the Tories on Brexit, he's sat on his hands.
We can only stop Brexit with the Labour party's votes. And the only way we get those votes is if they're scared of a pro-European tide sweeping them away.
With your help in Lewisham East, we can make them fearful of us. Will you come and volunteer in the final few days?
This by-election is your opportunity to make a difference - and help stop Brexit.
We are running rings around Labour in our activity. No other party is anywhere to be seen. Our stake boards are turning Lewisham East orange, we have canvassers on every doorstep and our leaflets can be found in every letterbox.
Lewisham Labour voters are not happy with Jeremy Corbyn. They were promised that he would stand up to the Tories on Brexit, but he has caved at every single opportunity.
Lewisham voters are willing to lend us their vote in this by-election to make it clear to Jeremy Corbyn that this isn't good enough.
And it couldn't come at a better time.
The stakes couldn't be higher.
The EU withdrawal bill is rumoured to hit the House of Commons any day now. A great result in Lewisham East for an unashamedly pro-European party would be a hammer blow to a hard Brexit.
But unless he's scared that remainers will stop voting Labour, he'll continue to take Remain support for granted.
Help us make sure he stands up to the Tories on Brexit. Help us send Jeremy Corbyn a message in Lewisham:
This could be your chance to change the direction of British politics.
When the dust has settled and the results are in, you will want to say you were in Lewisham East, part of the team making it happen.
Former leader of the Liberal Democrats