Video report by ITV News Political Correspondent Daniel Hewitt
By elections in marginal constituencies often attract protest votes.
Peterborough, where they are voting on Thursday, is certainly marginal - and as a Brexit voting area could be said to have plenty to protest about.
Last time, in the general election of 2017, it was a tight race in which Labour narrowly defeated the Conservatives.
This time it could be the Brexit party that wins - and produces its first MP.
For more than a century the safest bet you could place in Peterborough was on its people sending a Tory or Labour MP to Parliament, but not anymore.
The Conservatives lost the Peterborough seat in 2017 to the Labour candidate Fiona Onasanya but after being jailed for lying about a speeding offence - last month Peterborough became the first constituency to successfully petition to sack its MP.
ITV News Political Correspondent Daniel Hewitt visited a card club in the centre of the city old traditions are being tested.
Ken always voted Labour but he also backed Brexit and he's about to punish them on Thursday for failing to deliver it.
He said: "Labour's struggling because it's not really in alot of areas protecting the working man, has it? It's lost its way.
He added: "At the end of the day it will be a protest vote."
The Brexit Party won the European Elections here two weeks ago but the bookies favourite will have to do what Nigel Farage failed to do with UKIP here and beat Labour and the Tories in a Westminster election while facing a resurging Liberal Democrats.
Workers at a trailer manufacturer, which exports to the EU, are hoping whoever wins will spark new urgency in the Brexit negotiations.
Joshua Barnard, Manager at Lawrence David Trailer Manufacturer said: "We need to know what is going on so that we can keep taking orders, we can keep building trailers, we know where our stock is coming from - we know if it will come across The Channel or not.
"These are all things that are uncertain."