Russian President Boris Yeltsin dances at a rock concert after arriving in Rostov Monday. A new poll gives Yeltsin his biggest lead yet over Communist challenger Gennady Zyganov in the nation's presidential election Sunday. Yeltsin, who suffered two serious bouts of heart trouble last year, is trying to assure voters the energetic man they are seeing now is here to stay. But rivals are scoffing at Yeltsin's whirlwind campaign and nonstop promises. And many Russians worry that if the 65-year-old Yeltsin wins a second term, he might withdraw and govern through a filter of top aides.
