And it has now been claimed Labour's pledge to nationalise the railway could become more attractive to commuters fed-up with delays and cancellations.
The Liberal Democrats have sent a letter to bosses at West Midlands Trains, which operate services through the Black Country.
The company has come in for criticism recently and the Express & Star revealed last month almost a quarter of passengers were being forced to stand on its trains during morning rush-hour.
The Wolverhampton branch of the party said it was "unacceptable that people will have to continue on such a poor service".
Members also called on the company to "act before it is too late".
The Lib Dems said they "do not support that proposal but we understand the attraction some feel for it due to the service many are receiving."
Lib Dem campaigner Nick Machnik-Foster also said fares should be cut if companies can't provide reliable service.
He said: "Why should we pay full fare for trains that take three times too long.
"In the last few weeks it has been a nightmare for commuters and something has to give, and for once it should be commuters who see the benefits.
“The train companies are making us for a first-class service when people stand or even have to sit on the toilet to get a seat.
“It is time for the companies to cut the fares and give passengers a reward for sticking so loyally with them.”
West Midlands Trains says it is investing £700m into expanding its fleet to try and tackle overcrowding and other challenges.