Catholics for Labour, a new group launched this week at the party's conference in Brighton, is part of a wider drive to reconnect religious voters with Jeremy Corbyn's leadership.
Since Alastair Campbell's infamous and widely misunderstood 'we don't do God' line, there is a perception Labour is hostile to believers. Just this week the party's faith envoy Stephen Timms told Christian Today churchgoers received a 'lukewarm' welcome in the party and warned Labour 'desperately needs' more religious people.
'There is this sense of "please leave your faith at the door when you join us. You're very welcome to join us but please we're not interested in your faith,"' he told Christian Today.
Mike Kane, shadow schools minister and Timms' Catholic counterpart in Labour, agreed. He said there were 3.8 million Catholics in England and Wales and 'Labour ignores them at their peril', according to the BBC.
But for Kane, who is MP for the largely working class constituency of Wythenshawe in Manchester, it is not just about starting something new but reconnecting the party to its roots.
'There is a long tradition between the Labour movement since it started and the Catholic Church,' he told Christian Today in Brighton.
'Overwhelming since 1900 Catholics have voted in large numbers for the Labour party. If only Catholics voted Labour every time we would have a landslide majority.'
He's right. Data from the British Election Study reveals that Catholics have tended to vote Labour for several decades.
But they are losing their grip.
Polls show the support for Labour falling among Catholics and support for Conservatives rising, slightly. At the last election Labour's lead among Catholics was just two percentage points when it once stood at 40 in the 1990s.
And Mike Kane is looking to tackle that drift, launching Catholics for Britain alongside other senior Labour figures including Emma Lewell-Buck, Jon Cruddas, Stephen Pound, Keith Vaz, Conor McGinn, Andy McDonald and Sir David Crausby.
Opening with a mass at St Mary Magdalen, Brighton, on Sunday, Kane said there was standing room only as more than 150 packed into the small building.
'Already there is a real pace and real energy,' he told Christian Today. 'There was a real need for it.'
He went on: 'Our key objectives are to give a space for Catholics to participate in public policy debate in the public realm and to bring the rich vein of thought of Catholic Social Teaching to the debate.
'I am talking about human dignity, I'm talking about the preferential option for the poor, I'm talking about the care for creation, I'm talking about making sure the things we produce are for all the people and not just some.'
Inevitably Catholics will feel more comfortable with some aspects of Labour's identity – for example the emphasis on social justice – but less with other aspects. For example the party has a largely progressive, liberal approach to marriage and life issues.
But Kane said that was a false premise.
'The party has clear clauses on life issues,' he said, emphasising not all Catholics agree with the Church's stance on abortion and same-sex relationships. 'For those of us who are pro-life those clauses come into effect and we vote with our conscience on those issues.
'Catholics are free to vote as they wish.'
It isn't just specifically 'Catholic' issues the group will focus on. Overlooking the sea outside Labour's conference, the conversation turns to Brexit and Labour's divisions.
'The European Union was devised by a number of Catholic politicians,' said Kane. They were based on the principles of Catholic Social Teaching. To stop the continent going to war every few years we built a system based on solidarity but also subsidiarity.
'What has been hard about Brexit is seeing solidarity between nations break down,' he added.
'People have felt left behind in the EU debate and we need to see as Christians how we get people to re-engage with their communities, their government, and internationally as well because we are called to participate not just in our streets but across society as a whole and I think that includes Europe.'
Asked whether the group would use the Catholic instinct to support the EU to lobby for a softer Brexit he said: 'I think the principles of solidarity and subsidiarity will play heavy on Catholics in Parliament over how we go forward in exiting the EU. We shouldn't' be afraid to bring that voice to the table in the debate.'
Traditionally Catholics are left-of-centre economically but conservative on social issues. Kane's group could provide a bridge back to Labour's lost working class voters who baulk at the north London metropolitan liberals at the top of the party. After fighting off a strong UKIP challenge in the north-west to win his seat in a by-election, Kane knows all about the importance of Labour's socially conservative base.
But when it was suggested the Conservatives has successfully branded themselves as the party of the family and other socially conservative values, Kane was incensed.
'This has a government that has not seen pay go up in eight years. That puts immeasurable strain on families. This is a government that has taken away child benefit for families with more than two children. This is a government that has cut disability benefit and this is a government that has seen a huge rise in homelessness, in every city, in every part of our land.'
This is more than just a fight for a religious voice in Labour. It is a fight for the identity of the party.
Stephen Pound, another member of Catholics for Labour, told those gathered at the launch: 'I just do not understand how you can be a Catholic and not vote for Labour.'
The challenge will be convincing the UK's increasingly middle-class Catholic population to agree.
