By JESSE J. HOLLAND, Associated Press Writer 21 minutes ago Amid widespread rumors and speculation, senators are split on whether Chief Justice William H. Rehnquist will join Sandra Day O'Connor in retirement and give President Bush multiple appointments to the Supreme Court. O'Connor announced plans to leave the high court two weeks ago and speculation is swirling about the future of the 80-year-old Rehnquist, who has thyroid cancer. Sen. Arlen Specter (news, bio, voting record), R-Pa., chairman of the Senate Judiciary Committee, said senators had discussed with O'Connor a scenario under which she might consider changing her mind if Rehnquist...