MOSCOW (AP) — Moscow teenagers Kirill Strizhov and Alexander Pelevin have never known a Russia without President Vladimir Putin. Now, they say, the time has come for a younger leader.

While most of their classmates relax at home, the two dedicate their weekends to canvassing for opposition leader Alexei Navalny, the 41-year-old anti-corruption crusader who triggered mass protests this year when he released an investigation into assets, including opulent mansions in Russia and abroad, allegedly accumulated by Prime Minister Dmitry Medvedev.

Navalny declared his intention to run for president in the March 18 election, even though an embezzlement conviction he calls politically motivated officially bars his candidacy. He's organized a grass-roots campaign across the country and staged waves of rallies to pressure the Kremlin to allow him to register for the race. But authorities have so far shown no inclination to let him run, and Navalny has threatened to call for boycotting the vote.

Youth volunteers like Strizhov, 15, and Pelevin, 17, made up a large part of crowds who've marched in support of Navalny, from the westernmost city of Kaliningrad to Vladivostok in the Far East.

"A lot of young people watch Navalny's YouTube channel — it's a new, informative platform for us," says Strizhov, who volunteered full-time following the Medvedev investigation. He says that before he had been apolitical, but that "Navalny explains complicated subjects in a way that we can understand."

In today's Russia, there's a growing gap between the Soviet-born older generation — dependent on state television airing government propaganda — and Russia's Western-looking, tech-savvy millennials. Polls show Putin has the broadest support, however, including among the youth.

This discrepancy is no more apparent than when the boys visit apartment blocks on the city outskirts, trying to engage pensioners with Navalny's anti-Putin message.

"Look lad, vote for Putin, and all will be well!" shrieks an old lady as Strizhov tries to press a leaflet into her hand.

"Alexei Navalny is a homosexual, Western agent!" shouts another in a stream of expletives.

Pelevin's parents, Tatiana and Alexander, know the risks their son is taking in supporting the man who poses a very real, political threat to Putin. In 2012 their older son was detained and fined for joining massive rallies in Moscow against Putin's rule — the largest protests during his tenure.

Local news reports say Navalny volunteers and their families in towns such as Vladimir and Kemerovo have been threatened, intimidated and fired from their jobs. Last week, ultra-nationalists attacked his campaign headquarters in Chelyabinsk.

"I do suffer sometimes but I support his choice" says Tatiana, a painter. "Our children will only be able to live a normal life once this country becomes democratic and lawful."

Alexander, a geologist turned poet, and himself a vocal Navalny supporter, was surprised by how seriously his son takes his activism.

"He goes out canvassing and doesn't return until nine or 10 at night. exhausted!"

Navalny's supporters say his conviction was retaliation for political activity and assume he will run anyway.

"Navalny has returned real, street politics to Russia," said Sergei Boiko, a campaign manager, noting that regardless of what happens, the campaign has visibly inspired and mobilized thousands of young people.

"The main question is what's next?" said Pelevin.