Anti-corruption campaigner Alexei Navalny has long been the most prominent face of Russian opposition to President Vladimir Putin.
And last year he announced his intention to run for president in 2018, saying it was important to have a “clash of ideas” and a real choice.
But he may be forced to abort his plan after his conviction by a Russian court of embezzlement, which would bar him from any candidacy.
He denies the accusations, and says his legal troubles are Kremlin reprisals for his fierce criticism.
His rise as a force in Russian politics began in 2008 when he started blogging about alleged malpractice and corruption at some of Russia’s big state-controlled corporations.
One of his tactics was to become a minority shareholder in major oil companies, banks and ministries, and to ask awkward questions about holes in state finances.
His use of social media to deliver his message symbolises his political style, reaching out to predominantly young followers in sharp, punchy language, mocking the establishment loyal to President Putin.
‘Crooks and thieves’
The campaign against corruption took Mr Navalny from criticism of corporations directly to opposition to the ruling party, United Russia.
Ahead of the 2011 parliamentary election, which he did not fight as a candidate, he urged his blog readers to vote for any party except United Russia, which he dubbed the “party of crooks and thieves”. The phrase stuck.
United Russia won the election, but with a much-reduced majority, and its victory was tarnished by widespread allegations of vote-rigging that prompted protests in Moscow and some other major cities.