I believe that was in a Roll Call column by Mort Kondracke last week, because I saw it too. They must have limited that poll to the Bay area or to RATS. 8^)
However, it appears that one of three things is true. Either Harris didn't believe their own poll and discarded it, or it was a Harris poll that was done for a particular group and not made available to the general public, or Mort was mistaken. According to PollingReport.com, Harris has not had Bush below 70 in 6 months.