MOSCOW - Russians voted on Sunday in a parliamentary election expected to hand President Vladimir Putin a big personal endorsement, but opposition figures said widespread fraud undermined the vote's legitimacy.

Pollsters said Putin's United Russia party was expected to win a majority of up to 65 percent of votes, a show of public support which Putin hopes to use to establish himself as a powerful "national leader" even after he steps down next year.

Three other parties were likely to join United Russia in parliament but with dramatically smaller votes, while Putin's most vocal critics in the liberal opposition were expected to fall short of a 7 percent hurdle to enter the chamber.

Putin, 55, is riding high on an oil-fuelled economic boom and soaring popularity from a no-nonsense approach that has restored national pride with a big military build-up and harsh verbal attacks on the West.

He leads the United Russia party's list of election candidates but has not said what role he intends to play to keep influence after next year's presidential election. He said after voting he was in "festive mood."

In the Siberian village of Belovsky, local election officials brought a ballot box to the home of 94-year-old Sofia Kolesnikova because she was too frail to go out.

"My legs don't move, but my head works," she said. "Today I voted for Putin and for United Russia, because our president supports the young ... And what's more, as a man, how I like him!"

First official results and exit polls were expected shortly after the last polling stations closed in the western enclave of Kaliningrad at 8 pm local time (6:00 p.m. British time).

By 2:00 p.m. British time, turnout was 54.8 percent. Election chiefs said despite sub-zero temperatures in most of the country, the final figure would exceed 60 percent.

Analysts say the Kremlin needs turnout of at least that size to be able to present the vote as an endorsement for Putin.

FRAUD ACCUSATIONS

Opposition politicians and independent monitors Golos cried foul even before the polls closed, alleging numerous instances of electoral fraud.

In Moscow, the city election commission chairman said foreign observers had not reported any abuses. Voting was proceeding "calmly and according to schedule", said Vladimir Churov, chairman of the Central Electoral Commission.

This followed accusations -- denied by the Kremlin -- that skewed media coverage, intimidation of opposition parties and the liberal use of government resources to promote United Russia had made the contest one-sided even before polls opened.

"These are the dirtiest, most irresponsible elections," Communist Party leader Gennady Zyuganov said. "... They have thought up at least 15 ways to entrap and betray voters".

Former world chess champion and opposition icon Garry Kasparov denounced the election after intentionally spoiling his ballot paper at a snowbound central Moscow polling station.

"They are not just rigging the vote, they are raping the whole electoral system," Kasparov said. "These elections are a reminder of Soviet elections when there was no choice." Kasparov has little popular support inside Russia.

ECONOMIC BOOM BOOSTS PUTIN

The opposition's complaints were irrelevant for many of the 106 million registered voters. Russians have enjoyed an oil boom under Putin that has boosted wages and living standards.

"I remember how we lived before, and it has only been under Putin that the country has picked itself up," said Tatyana, a 61-year-old actress who declined to give her family name.

The West's main election watchdog, the ODIHR, was not monitoring the vote, creating a headache for foreign governments which normally rely on its judgment about election fairness.

The ODIHR pulled out after a row with Moscow over delays in issuing visas. Fewer than 300 foreign observers, half from former Soviet republics, have been accredited for the election.

Putin has said the election will be "honest, as transparent as possible and open". He has told Western governments to keep their "snotty noses" out of Russia's affairs and stop trying to undermine the election.

Election monitors Golos said they had collected reports of violations ranging from police detaining observers to groups offering gifts in exchange for a pro-Putin vote.

In the second city of St Petersburg, a party competing against United Russia said people were being bussed around the city voting in one polling station after another. One Kremlin opponent said he saw one such bus being driven by a policeman.