Alexei Navalny is a social media sensation. His anti-corruption videos have made him popular with many young Russians.

And now he wants to run for President in March 2018... but he's got some big challenges ahead.

BBC Trending goes inside Alexei Navalny's social media machine. How has it transformed Russian politics?

Watch Part 1: Meet the people battling online for Russia's future

Producer: Kate Lamble

Video journalist: Alex Dackevych

Additional camera: Irina Sedunova

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