The Liberal Democrats are preparing to announce whether Tim Farron or Norman Lamb will be the party's new leader.
Tim Farron is the new leader of the Liberal Democrats, the party has announced.
Voting has closed in the race to replace Nick Clegg, who resigned after a disastrous general election that left the Lib Dems with just eight MPs.
The former part president beat Norman Lamb in the contest to replace Nick Clegg.
The winner, who will be announced on social media at about 17:00 BST, will then address a party rally in central London.
Mr Farron, whose victory was announced on Twitter, is to make his first public appearance as leader at a central London rally later.
Mr Farron, the former party president, is the bookmakers' favourite.
The left-leaning Westmorland and Lonsdale MP has said he wants to focus on rebuilding the party from the grassroots up, and on issues such as human rights, the environment, and building a "fairer and more equal society".
Mr Lamb, a health minister under the coalition government, said he wanted the party to be a "consistent and clear voice" standing up for a liberal society.
After a post-election surge in membership, over 60,000 Lib Dem members were eligible to vote.
Counting is under way, with the votes being sorted into batches of 100, the Lib Dems said.
Former Lib Dem chief secretary to the Treasury Danny Alexander, who lost his seat in May, used a New Statesman article to urge the winning candidate to occupy the centre ground, and not become a "sort of soggy Syriza in sandals" - a reference to Greece's anti-austerity government.
Mr Alexander said the party should not make George Osborne's Budget a "political dividing line" but instead should attack the Conservatives over civil liberties and the environment.
Tim Farron
Mr Farron, a 45-year-old father of four, is popular with activists for his tub-thumping party conference speeches and easy-going manner, but he has not always been regarded with similar affection by party elders.
After suggesting the Lib Dems deserved only two out of 10 for its performance in government, he was rebuked by, among others, former leader Lord Ashdown, while former deputy leader Vince Cable very publicly questioned his judgement.
Mr Farron always insisted he had been referring to the party's handling of coalition relations and the wider politics involved rather than its achievements in power but it was taken by some as evidence of disloyalty and future ambition.
Profile: Tim Farron
Norman Lamb
Unlike his rival Tim Farron, Mr Lamb, a 57-year-old father-of-two, was a minister in the Tory-Lib Dem coalition for three years and is personally associated with the controversial decisions on spending, tax and welfare which many activists blame for its worst election result in its history - in which only Mr Lamb and seven colleagues survived.
Although he has vigorously defended the decision to join forces with the Conservatives, saying the party acted in the national interest at a time of economic crisis, Mr Lamb has conceded the party made "stupid mistakes" during its five years in power.
The party, he admits, was not "ruthless" enough in its dealings with its partners, failing time and again to gain credit for popular policies and to get across to a sceptical electorate why unpopular decisions were necessary.
