As we reported last week, the field of candidates for the three open at-large seats on Knoxville City Council is large and boisterous. But it has become a little less large in recent days. First there was the announcement by local radio host Hubert Smith that he would not run for At-Large Seat A, because it would have meant giving up his weekly show on WUTK. Tuesday brought another withdrawal: Tierney Bates, the young UT administrator who ran unsuccessfully for the 2nd District Council seat in 2009, says he is leaving the race to help care for an ailing relative. Bates’ name will still appear on the ballot for At-Large Seat B, but he is encouraging supporters to vote for another candidate of their choice.