An article on bodybuilder.com had a top ten list of the 'strongest states' in the country. They came up with the list from the over eight million people who are members of BodySpace, a website that users list their personal best with bench press, deadlift and squats. This top ten list is a combined average for everyone in that state, men and women combined. Here's the top ten list.

1. South Dakota: Bench: 161.5 Deadlift: 195.4 Squat: 221.4
2. Iowa: Bench: 163.7 Deadlift: 206.2 Squat: 195.1
3. West Virginia: Bench: 167.9 Deadlift: 202.4 Squat: 194.1
4. Nebraska: Bench: 158.9 Deadlift: 199.8 Squat: 198.6
5. Louisiana: Bench: 151 Deadlift: 179.6 Squat: 223.9
6. Maine: Bench: 158.8 Deadlift: 218.6 Squat: 176.8
7. North Carolina: Bench: 159.9 Deadlift: 195 Squat: 199.2
8. Montana: Bench: 168.4 Deadlift: 193.4 Squat: 191.3
9. Vermont: Bench: 134.2 Deadlift: 241.8 Squat: 174.8
10. Indiana: Bench: 160.6 Deadlift: 196.3 Squat: 192.4

The article also mentions the Central Maine Strongman competition held annually at the Augusta State Armory. That's where I found this article, from the organizer of that event, Dana Geneseo.