Hi Oksana, regrets for the belated reply. Thanks very much for your exemplary engagement.
Regarding Beshear, he can go into the Midwest and Rustbelt states and attract blue collar white voters who are undecided or leaning toward Trump. His background as a two-term governor in ruby red conservative Kentucky makes him unique to deliver Kamala's message to this crucial voting bloc which will likely decide the election.
Please note that, historically, vice presidential nominees do NOT carry their home states for the ticket. Sometimes, they do, but a lot of times they don't.
I'm not saying Kamala won't pick Shapiro or Whitmer, but I would be surprised. She has a close 20-year relationship with Gov. Roy Cooper of NC. Choosing him would make NC competitive, and winning NC would open more avenues to 270 in the electoral college. Plus, Cooper has excellent political acumen and stature to appeal to undecided white voters--some of which Kamala needs to win.
Mark Kelly is another good choice due to his resume and being from Arizona, where he can address immigration--and perhaps deflect all the attacks about the border by Trump.
One thing is for sure, it's definitely a tough decision.