Andy Flanagan from Christians on the Left - a group affiliated to the Labour party - told Premier News Hour that "nobody was pretending it was a good day" but that the resignation created space for "wonderfully talented" candidates to stand in the upcoming by-election.
"As Christians on the Left we have been training a fantastic bunch of candidates that are getting stuck in and standing for election," said Flanagan, "As people move on it creates space for a lot of these wonderfully talented folks who we've been training who desperately want to put their faith into action and stand for the principles they believe in. It's a great time for Christians to show up in politics."
UKIP are expected to do well in the upcoming by-election for the seat in Stoke-on-Trent Central.
In the 2015 general election, the right-wing part came second. The constituency also voted overwhelmingly to leave the EU in the referendum last June.
"People feel let down by globalism," said Flanagan, "UKIP absolutely stand a chance, people feel their country is sliding away. When politicians get too far away from the people that they are leaving it's not a healthy thing.
"Christians on the left have been saying we need to reconnect with the breadth of society. We need to encompass the views of everybody."
Listen to Aaron James speak to Andy Flanagan here: