MOSCOW (AP) _ A tumultuous five years after abandoning communism, Russians voted today in a presidential runoff that will determine whether the world's largest country pushes ahead with democratic reforms or reverts to Soviet-style controls.

President Boris Yeltsin smiled and looked confident as he was shown on state television voting near his country home. However, his failure to appear as scheduled at a Moscow polling station raised new concerns about his health and ability to govern should he defeat Communist leader Gennady Zyuganov.

Yeltsin's often-shaky health threatened his campaign when he canceled public appearances during the final week. But he went into the vote the favorite in a country that has endured but not prospered under his wrenching free-market reforms.

Voters faced a stark choice in Russia's first presidential vote as an independent country: Yeltsin, and an endorsement of Western-style democracy. Or Zyuganov, and a return to more restrictive ways.

Thousands of armed guards patrolled Moscow's polls and subway. Huge Russian flags hung from buildings along boulevards. Banners and posters everywhere urged people to vote. Nervous, pro-Yeltsin Muscovites said they wouldn't sleep until they knew the outcome.

Zyuganov told journalists that early reports from his election observers were encouraging. Of Yeltsin's health, he said that ``in the last four or five days he hasn't seen anyone except his inner circle. ... It shows the situation isn't very good.''

Scores of journalists waited for hours for Yeltsin to appear at a polling station in northwestern Moscow. But aides said the president was recovering from a cold and decided to take a break from the constant media attention by voting quietly near home.

``It was his decision. It's closer,'' Prime Minister Viktor Chernomyrdin said of Yeltsin's voting instead in the small village of Barvikha outside the capital. He gave few other details, saying ``I think everything is OK.''

``For half a year, he's fulfilled his meetings with the press 120 percent,'' and this time the president should be excused, Yeltsin's spokesman, Sergei Medvedev, said.

Yeltsin urged Russians to come to the polls. ``Don't forget about your duty. Come and vote,'' he said in state television footage.

On the Pacific coast some 4,000 miles from Moscow, turnout was about 35 percent by early afternoon, down from 39 percent at the same time in the first round of voting June 16.

Regional officials blamed the low turnout on sunny weather and the morning airing of a three-hour episode of a favorite South American soap opera, ``Tropikanka.'' A national holiday was declared for the election, and a wave of voters was expected in the evening, however, when people return home from country homes, or dachas.

Yeltsin's forces hoped for a large turnout among the country's 108 million eligible voters to carry him past the Communists' rain-or-shine voters. His campaign said a turnout of 60 percent or less _ down significantly from 69.8 percent in the first round _ could give Zyuganov the race.

But by early afternoon, Yeltsin aides expressed concern that turnout was lagging behind that of the first round. Top officials, including Chernomyrdin and Moscow Mayor Yuri Luzhkov, urged people to vote.

A simple majority is all that's needed for victory. The first results from the 93,500 polling stations across 11 time zones were expected late today.

``There's no other choice but Yeltsin because there is no one else who can continue reforms,'' Adolfovich Baryshnikov, a 62-year-old construction engineer, said after voting in Vladivostok.

Another voter said she was for Zyuganov but didn't want to talk about it _ typical of many Communist supporters who are reluctant to reveal their sentiments. She left the polling station in tears.

Kremlin aides spent the last days of an intense and bitter campaign denying that the 65-year-old Yeltsin was stricken with more heart problems, saying his voice had simply given out from too many interviews. But the president who bounced and danced through a vigorous first-round campaign looked stiff and wooden in a televised appeal to voters Monday.

Yeltsin's virtual disappearance left an opening for Zyuganov, 52. But his recent attempts to publicize the issue of the president's health across Russia were stymied by the openly anti-Communist media, most of whom ignored it.

Many Russian voters remain unaware that the president is sick again, and those who have supported him appear unfazed by the news.

``What's going on _ Yeltsin's too sick to come?'' Vladimir Polosukhin, a 61-year-old voter, asked some of the reporters milling around the polling place where the president had been expected to vote.

``Let him be sick. We'll vote for him all the same,'' said Polosukhin, who said Yeltsin's reform policies are what matters.

Zyuganov failed to reach many new voters in the first round, in which Yeltsin outpolled him 35 percent to 32 percent, or to form alliances afterward. His appealed to hard-liners rather than to Russia's political center, and he shunned Western-style media hype in favor of his party's grassroots organization.

Yeltsin, meanwhile, took steps to seal a victory immediately after the first round, bringing third-place finisher Alexander Lebed aboard as national security chief. Analysts predicted a majority of the former general's 11 million voters would back Yeltsin in the runoff.

Russia's first elected president, Yeltsin started out the year extremely unpopular for his painful economic reforms and for starting the war in Chechnya. But he outmaneuvered other candidates in the 10-man field with a media-savvy campaign that leaned heavily on the powers of incumbency.

Zyuganov seeks the ``voluntary'' restoration of the Soviet Union and has vowed to restore many features of Soviet rule, from increased economic controls to clampdowns on the press and Western culture.