Spencer Pratt — the 2000s reality TV star turned 2010s online influencer turned 2020s populist firebrand — is now a formidable candidate in the L.A. mayoral race, gauged by fundraising totals, poll numbers and incoming criticism from chief rivals. This ascent is a shock for the city’s liberal establishment, which considers him an unqualified clown. It shouldn’t be. His reactionary run, a revivalist pitch to make the city “once again ‘camera-ready’ for all its citizens” by cracking down on crime and corruption, has gained traction with his rollout of a slick and mischievous digital strategy. It culminated in a recent campaign ad rollout riffing on Kendrick Lamar’s “Not Like Us” to knock his competitors, incumbent Mayor Karen Bass and progressive L.A. City Councilmember Nithya Raman. The button on the spot was a callback to his own Act I inciting incident — how his house burnt down in last year’s Pacific Palisades wildfire as a result, he insists, of government incompetence. Pratt posted his most revealing meme three days earlier, on April 26: Himself embodying Michael …