Political parties: Who joins them these days?
In an age of disillusionment with mainstream politics, you could be forgiven for thinking that fewer people then ever are joining political parties.
In fact around one in 50 people in the UK is a member of one of the three main UK political parties - Conservative, Labour or Liberal Democrat.
That's roughly double the number in 2013 when membership was at a historic low.
But what do we know about those who sign up?
New research given to BBC Reality Check shows there's a growing divide between the Conservative and Labour membership since Jeremy Corbyn became Labour leader in 2015.
Tim Bale, professor of politics at Queen Mary, University of London, and colleagues both at Queen Mary and the University of Sussex have surveyed 1,000 Labour and 1,000 Conservative members following the 2017 general election for the Party Members Project.
Professor Bale says Labour has added an "astonishing" number of members since Mr Corbyn became leader two years ago - up to 552,000 members as of June 2017 - an increase from 388,000 since the end of 2015, giving it a higher membership than it had under Tony Blair's leadership.
Professor Bale's data reveals that Labour has had particular success in attracting women, and the party is close to achieving a 50-50 gender balance.
That contrasts with the Conservatives, where around 70% of members are male.
Labour Party joiners tend to be typically in their mid-to-late 50s.
They are also overwhelmingly middle-class and the majority work in the public sector.
Professor Bale says a significant number of new members are "retreads" - former members, typically from the 1980s and 1990s, who left under Tony Blair and returned during the last two years.
"Labour does better than the Conservatives when it comes to young members, but in terms of the bulk of people that joined Labour since Corbyn's election, around a third are former members," he explains.
They include Manchester-based Lauren, who is part of the city's Labour Women Forum. She says she feels as though she's "got my party back".
"I struggled with my support for Labour when Labour went into the Iraq war," she said. "Two years ago when Jeremy Corbyn became party leader I joined the day after."
The Conservatives, in stark contrast, have seen membership stagnate. The party has not released any data since 2013, when there were 150,000 members.
But Prof Bale believes their membership has come down a bit since then.
But the headline number masks what he sees as a bigger problem.
"Around 40% of Conservative members are over 65 and very few are in the 18-40 age bracket," he says.
The data also reveals that Conservative members, like Labour, tend to be overwhelmingly middle-class.
When it comes to campaigning, Conservative members were less active in the 2017 general election, according to Prof Bale's research:
"What is most striking is the fact that Tory grassroots members did less on almost every count than their counterparts in other parties - and sometimes significantly."
How active were party members during the election?
|'Like' something on Facebook||38||63||62||71|
|Displayed a poster||24||56||49||59|
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|None of these||23||9||10||8|
Source: Party Members Project, Queen Mary University of London and Sussex University
How is the Conservative party responding?
MP George Freeman, chairman of the prime minister's policy board. has the task of developing ideas that will renew the grassroots and attract new members.
He says: "Clearly there's a real problem and it's now quite urgent. The age issue is really important. We have a very strong senior-citizen wing. We've neglected our under-40 membership.
"If we only talk to those over 60 we will end up only talking to ourselves. This is a real challenge that we're all gripping."
Mr Freeman believes that the party needs to alter its campaigning message in order to attract new followers.
He organised the Big Tent Ideas Festival as a way to get younger people interested in Conservatism and to come up with ideas to shape party policy.
The Conservatives still retain the financial advantage, courtesy of donors.
In the three months running up to the general election the Conservatives received almost £25m in donations - more than half that of all the other parties combined.
With such financial clout, does party membership matter?
For Professor Bale it continues to be an essential part of democracy.
"Most people join political parties because they agree with them ideologically and they have a sense of civic duty," he said.
"They feel they're the kind of people that can make a difference."