SACRAMENTO - A lawmaker who had called for Education Secretary Richard Riordan to resign for joking with a 6-year-old that her name meant ``stupid, dirty girl'' abruptly backed off Thursday after mistakenly suggesting that race was a factor in the quip. Assemblyman Mervyn Dymally, D-Los Angeles, canceled a news conference today with civil rights groups after learning that the girl subjected to Riordan's joke was white, not African-American. An aide to Dymally said the assemblyman had seen conflicting news accounts of the girl's race. In a press release canceling the news conference, Dymally, who is African-American, said Riordan had apologized...