Polls ahead of Sunday's election in Russia predict former president Vladimir Putin will win by as much as 60 percent of the vote.

One hundred and ten million Russians, including 2 million expats, are eligible to vote for one of the five presidential candidates: Prime Minister Vladimir Putin, Liberal Democrat Vladimir Zhirinovsky, Communist Party candidate Gennady Ziuganov, Just Russia party leader Sergei Mironov and billionaire Mikhail Prokhorov.

Putin stepped down in 2008 after serving two consecutive terms, the maximum according to Russian law. Many analysts viewed President Dmitry Medvedev as Putin's stand-in. Should Putin win the election, he has said he will appoint Medvedev prime minister.

Protesters opposed to his reentry to the presidency alleged electoral fraud and demanded reform.

"This is not an election…it is an intimidation," said Boris Nemtsov, one of the opposition leaders, The Associated Press reported.

In December, tens of thousands of Russians took to the streets of Moscow in the largest public opposition rallies in more than two decades. The street protests represent a public who has grown weary of Putin's dominance in Russian politics.

Should the 59-year-old former KGB agent be declared the winner, anti-government protesters plan to resume demonstrations as early as Monday.

"These elections are not free," said Mikhail Kasyanov, who served as Putin's first prime minister and is now in the opposition. "That's why we'll have protests tomorrow. We will not recognize the president as legitimate."

Natalya Yulskaya, 73, who voted for Prokhorov, said she knows the "KGB will be in power…but I gave it a try."

Many analysts say the political environment for Sunday's elections has changed for the first time since the collapse of the former Soviet Union.