Although his political account bulges with $4.7 million in cash and he has no opponent in sight, US Senator Edward M. Kennedy is on a fund-raising rampage from coast to coast, a campaign that Democratic supporters say is designed to leave him without a Republican opponent for the first election in his four decades in the Senate. The Kennedy fund-raising bandwagon comes to Boston March 4, when the senator and his family are throwing a birthday party for him expected to raise at least $500,000. Kennedy, who is turning 73, is pressing the state's Democratic establishment for the event that...