Anecdotal reply. I worked for an amazing LtCol in the USMC. We were chatting one day and I asked him when he might be putting on full bird. He looked at me dead serious and said " It will never happen,. I'm not PC enough or in with the right people."

Broke my heart. This was a man that I wouldn't hesitate to follow into hell with a water pistol. Of all the leaders I ever served under I would recommend him for 4 Star general. Total shame that someone like him won't be promoted because "wrong think" even invades the military.

Edit: Also yes, in my experience the average LtCol will do anything for that promotion. Anything.