MOSCOW — Openly defying Russian President Boris N. Yeltsin, residents of Tatarstan flocked to the polls Saturday for a referendum on self-rule that posed the most serious challenge yet to the unity of Yeltsin's sprawling Russian Federation.
Mintimer Shaimiyev, president of the oil-rich region of 3.7 million people on the Volga River, insisted as he went to cast his ballot that Tatarstan was not seeking to secede from Russia.
"We have never posed the question of leaving the Russian Federation, and we advocate a close union with it," the burly former Communist Party leader said, according to the Itar-Tass news agency.
Anvar Baugadinov, a member of the Tatarstan Election Commission, said early and incomplete returns were running 61% in favor of the referendum.
Tatarstan, about the size of Ireland, is one of a number of so-called "autonomous" areas scattered across Russia.
Yeltsin asserted in a televised appeal to Tatarstan residents Friday night that the referendum's results would inevitably be used as the basis for a secession attempt and would also probably set off outbreaks of ethnic strife.
"As president, I ask you to remember that the price of a political mistake is always concrete," Yeltsin said. "Our loved ones, families and children, will suffer first because of it."
Although Tatarstan's population makes up less than 3% of Russia's 150 million people and only a tiny fraction of its vast territory, the referendum evoked deep anxiety among Russian leaders because its form is so reminiscent of the first political cracks that led to the demise of the Soviet Union.
Tatarstan's insistence on going through with the vote also discredited the fledgling Russian Constitutional Court, theoretically the highest legal body in the land, which had ruled that the referendum's wording was unconstitutional and that the vote was illegal.
Complete results of the voting are expected today. Most predictions had been that a narrow majority would opt for self-rule.
The Russian government has not specified how it will respond to the referendum's outcome, but spokesmen have indicated that it does not plan an immediate show of force or punitive economic moves.
"As far as I know, no drastic economic sanctions, like blocking supplies or stopping the delivery of money, will be effected," Alexei V. Ulyukayev, a top Russian government economist, said last week.
Last November, when the rebellious republic of Chechen-Ingushetia held illegal elections, Yeltsin at first declared a state of emergency there and began to send in troops, then was forced to back down. In contrast, he has shown marked restraint in the confrontation with Tatarstan.
But the referendum appeared to demand a strident response from the Russian government if only to stem a new wave of separatism that could rise just as Yeltsin seems, at long last, to be cementing the country together.
Except for Chechen-Ingushetia and Tatarstan, all the rest of Russia's 31 autonomous regions had agreed last week to sign a new Federation Treaty, dividing power between local governments and Moscow.
A similar treaty among the republics of the old Soviet Union proved to be the undoing of former Soviet President Mikhail S. Gorbachev.
Reports from Kazan, Tatarstan's capital, said that voting took place peacefully, with a turnout of about three-quarters of eligible voters.
Only 48% of Tatarstan's population are ethnic Tatars; of the rest, 43% are Russians who had to decide between the "no" vote dictated by their ethnic allegiance to Moscow and a "yes" vote that could make their home republic richer.
Tatarstan produces 30 million tons of oil a year, and its officials acknowledge that their main goal in seeking greater sovereignty is to gain a bigger cut of oil profits by controlling trade and levying taxes.
Following the example of a slide toward secession set by the Baltic states, Tatarstan declared its "sovereignty" last August and has since asserted that its laws take precedence over the Russian legal code.
The referendum measure does not actually mention secession. Its text asks only, "Do you agree that the republic of Tatarstan is a sovereign state, a subject of international law, building its ties with the Russian Federation and other republics and states on the basis of equitable relations?"