The marathon contest to replace Rishi Sunak as Conservative leader is nearing its end, with the ballot of party members closing at 17:00 GMT today.
The winner of the race will be announced on Saturday morning, almost four months after the crushing general election defeat that triggered Sunak's resignation.
Tory members are choosing between former Business Secretary Kemi Badenoch and ex-immigration minister Robert Jenrick, after four other candidates were eliminated in a series of votes by the party's MPs.
Badenoch is the favourite to win, but Jenrick has insisted the contest is "close", saying "we're chasing down every vote".
Immigration, the economy, and how the Conservatives can rebuild trust with voters have been debated at length through the campaign.
The party suffered its worst general defeat in its history in July as it was reduced to a record low of 121 seats in the House of Commons, with under 24% of the vote.
Priti Patel, Mel Stride, Tom Tugendhat and James Cleverly spent the summer campaigning alongside the final two, after they put their names forward for leader.
Patel and Stride were eliminated in September, followed by Tugendhat and Cleverly after the party conference in Birmingham.
Cleverly was regarded as having performed best at the conference and topped the third MPs' ballot.
But he was surprisingly knocked out when Tory MPs voted for the final time 24 hours later. Badenoch secured 42 votes, Jenrick 41 and Cleverly 37.
A survey of Tory members by the ConservativeHome website last week suggested Badenoch led Jenrick by 55% to 31%, with a further 14% undecided.
Jenrick, who resigned from Sunak's government in protest at its approach to tackling migration, has put the issue at the centre of his leadership bid.
He has called for a legally-binding cap on net migration, and for the UK to leave the European Convention on Human Rights which he argues had made it "impossible to secure our borders”.
He has also repeatedly criticised Badenoch for refusing to set out detailed policies during the campaign.
Jenrick told GB News the Conservatives "lost four million voters to Reform at the last election" and it was "going to take a lot" to persuade them to come back.
“That's why I say we're going to have to change the party fundamentally, and this time actually deliver, because we didn't deliver on some of those big questions.
“I think just saying that we will think this through, we'll come forward with policies in the months or years to come, isn't going to cut it."
Badenoch has called for a return to core Conservative values, arguing the previous Tory government "talked right but governed left".
She backs a smaller state with government doing "fewer things" but doing them better.
And she has countered Jenrick's criticism of her by arguing that the party needs to first decide what it stands for.
She told GB News: “We need to get back to first principles. We ended up talking about policy without rooting it in principles."
Badenoch also condemned the Budget as one that would destroy jobs and lower wages.
She described the government as “Jeremy Corbyn’s Labour with Keir Starmer fronting it”.