Tim Walz speaking at a campaign event in Detroit on Wednesday with Kamala Harris. Andrew Harnik/Getty ImagesIn work boots or a rumpled suit, Tim Walz has won some fans with his folksy fashion sense.Experts told BI his authenticity targets the very voters Harris needs.The Trump-Vance ticket is telegraphing more traditional power aesthetics, they said.In his video introduction to the world as Kamala Harris' running mate, Tim Walz wore white sneakers, khaki pants, a black T-shirt, and, of course, a signature camo cap.The now-viral video cuts between Walz, holding his phone on a chair, and Harris, sitting in an office.