Democrat candidates for California governor are irate over a last-minute decision to ax a scheduled debate — over claims of racism. University of Southern California pulled the debate, scheduled for Tuesday evening, after complaints by low-polling Democrats that they were excluded because of their race. Democrats are increasingly anxious about the possibility of two Republicans — Hilton and Riverside Sheriff Chad Bianco — advancing to the November general election as Democratic voters remain heavily splintered. Hilton is leading the field in recent polls, with Bianco not far behind.