Convicted opposition leader Navalny vows to win Moscow mayor's race July 20, 2013 -- Updated 0937 GMT (1737 HKT) "We are a huge, powerful force," Navalny tells crowd in Moscow Opposition leader is facing a five-year prison term Navalny will appeal his conviction, denies he misappropriated money in a lumber deal He vows not to waver again about finishing mayoral campaign (CNN) -- Russian opposition leader Alexei Navalny, facing a five-year prison term and free pending an appeal, returned to Moscow on Saturday and vowed he will be elected mayor. Hundreds of supporters and journalists met Navalny's train as he returned from his trial in Kirov, according to state-run Ria Novosti. "We are a huge, powerful force," Navalny told the crowd. I'm very glad that we've started to recognize that force ourselves. ... I want to apologize to you for not believing so strongly in you. His apology referred to his statements Friday that he was not certain he would run for mayor. By Saturday, he was declaring, "We will go to the elections and we will win," Rio Novosti reported. Navalny was detained overnight Thursday after a court in Kirov city found him guilty of misappropriating about $500,000 in a lumber deal when he was an adviser to the region's governor. He was released Friday. Navalny denied wrongdoing and said he was targeted because he is one of Russian President Vladimir Putin's most outspoken critics. Navalny has been a prominent organizer of street protests, and has attacked corruption in Russian government. "Navalny's prosecution is meant to silence a leader and messenger," said Rachel Denber, deputy director of Human Rights Watch's Europe division