WARSAW, NOV. 21 -- The race for the Polish presidency suddenly has a third man.

Stanislaw Tyminski, a Polish-born businessman who claims to be worth $5 million, has rocketed from obscurity to a four-point lead over Prime Minister Tadeusz Mazowiecki in the latest voter preference poll. In survey results released today, he trailed front-runner Lech Walesa by only seven points.

On the stump, Tyminski enchants voters with tales of how he left Poland with $5 in his pocket and got rich in Canada and Peru. Then he fires off sweeping accusations against Mazowiecki and Walesa.

This week, after he angrily accused Mazowiecki of "treason," the Solidarity-led government threatened to sue for slander. All five of his opponents in Sunday's election have denounced him.

Still, Tyminski's rallies draw larger crowds than the prime minister's, and his rise in national opinion polls is nothing short of astounding. The latest poll showed Tyminski winning 21 percent of the vote. A month ago, few Poles had even heard of him.

Under rules of the presidential election here, if no candidate gets more than 50 percent of Sunday's vote there will be a runoff between the top two finishers.

Tyminski's splenetic campaign -- as it conjures up conspiracy theories about how Mazowiecki and Walesa are working with Communists and the World Bank to sell out Poland to foreigners -- appears to be tapping into a deep well of frustration in the electorate here.

Since the overthrow of communism last year, the already meager living standard of many Poles has declined further. Prices have soared as wages remain static. Many former Communists are still in charge of state-owned enterprises. Unemployment has surged past 1 million.

By blaming all this on the dark machinations of sell-out politicians, former Communists and foreign investors, Tyminski offers dispirited voters an easy scapegoat. By telling them that Poland needs nuclear weapons, Tyminski plugs into a small but rabid strain of Polish nationalism.

At his rallies, many Tyminski supporters describe their candidate as a "fresh face."

Tyminski, 42, tells voters that he left Poland when he was 21 and, during 10 years in Toronto, established an industrial automation firm. He says he lived for four years in the Amazon River port of Iquitos, Peru, building a cable television company.

Tyminski, who owns a mansion near Warsaw, says he is the founder of the Libertarian Party in Toronto, which he says has 3,500 members. But leaders of Polish organizations in that city say he was never active in the immigrant community.

The candidate says he earned $550,000 last year and is "very proud" of his wealth. He says he is paying for his campaign himself.