Just under 200,000 people will decide who becomes the new leader of Britain's ruling Conservative party and prime minister.
The following on the Tory electorate is largely based on a research initiative -- the Party Members Project (PMP) -- by Queen Mary University of London and Sussex University, published in 2020.
Size
Conservative party headquarters has yet to provide an up-to-date number for members eligible to vote in the contest.
A spokesman has said it would be more than the approximately 160,000 who voted in the last leadership contest, which selected Boris Johnson in 2019.
The then-party chair Amanda Milling said last year that the number had grown to around 200,000, a number confirmed by senior Tory MP Bob Blackman.
Those who joined the party at least three months before the latest ballot are entitled to vote.
They have until September 2 to cast their vote, either by post or online, and the result will be announced on September 5.
The UK is a parliamentary democracy, so the leader of the biggest party gets to be prime minister, with no requirement to hold a general election if the leadership changes mid-term.
Given the UK has a population of 67 million, that means less than 0.3 percent of people will choose its next leader.
Age, gender, ethnicity
Conservative members are older, whiter and more likely to be male than the national averages.
Nearly two-thirds are men, compared to an almost even gender split across Britain.
The biggest proportion -- 39 percent -- are over 65, with another fifth aged between 50 and 64.
Less than 20 percent of the British population are aged 65 and over, according to the Office for National Statistics.
The Tory grassroots are also overwhelmingly (96 percent) white, more than 10 percentage points higher than the overall population.
Brexit
Britain's 2016 referendum saw voters split 52-48 percent in favour of leaving the European Union. But Conservative members skew far more towards Brexit.
Around three-quarters are "Leave" supporters, according to the PMP research.
Foreign Secretary Liz Truss supported "Remain" in 2016 before becoming a zealous Brexit convert, and is the frontrunner in recent polls of the grassroots.
Social class
Conservative members are generally richer than the wider electorate.
According to pollsters YouGov, around 57 percent of Britons are in the "ABC1 category" -- a social grading classification often used as shorthand to refer to the middle and upper classes.
But fully 80 percent of grassroots Tories are in this demographic.
Geographic spread
The party's membership is largely concentrated in southern England -- where only just over a third of mainland Britain's population lives.
More than half of members -- 56 percent -- live in London and the rest of the south, with only a fifth residing in northern England and just six percent found in Scotland.
Leadership qualities
Personal traits of the candidates rather than their specific policy pledges were cited as deciding factors in YouGov polling of members this month.
Following Johnson's scandal-tarred tenure, half of the membership surveyed said "honesty and integrity" were important in a new leader.
On policies, members most commonly said they wanted a return to "conventional conservatism", with an emphasis on cutting taxes and state spending.
That tallies with Truss's platform, while her main challenger, former finance minister Rishi Sunak, is focused on balancing the books after the Covid pandemic.