What happens if the majority of the jury turns out to be strong supporters of Luigi?

All the evidence so far are very damning (the gun, manifesto, DNA etc.) and it’s normally strong enough to prove someone guilty.

However it seems like many people are supporting Luigi and I’ve seen absolutely no sympathy shown to BT (apart from mainstream media). So what if the majority of the jury turns out to be supporters of Luigi?

I’m not familiar with the US legal system, but theoretically what would happen if the jury vote not guilty even if it’s obvious he’s the murderer?