While Los Angeles Mayor Karen Bass drew enough votes in Tuesday’s primary to advance to a runoff, first-time candidate Spencer Pratt was still duking it out with City Councilmember Nithya Raman on Thursday for the second spot on the Nov. 3 ballot. Whether Pratt makes it to the runoff or not, his insurgent bid may mark a sea change in political campaigns, largely around how he and his supporters employed provocative, and often effective, AI ads to spread his message.  Pratt, a Republican, was once a reality star villain—gracing televisions in MTV’s The Hills in the 2000s and eventually competing in the British version of Celebrity Big Brother twice with his wife, Heidi Montag. He launched his bid for mayor earlier this year with no prior political experience.…