Hell yes it does! I'm noticeably more upbeat and vivacious after a win. I watch the other games (if we played early) and am fully engaged.
A loss, and it usually takes a couple days for the sting to start to go away, and the rest of the week for it to fully subside. I have to force myself to watch the other games that day, and the whole time I'm reminiscing on our loss.
It's really bad if we lose on a Thursday, having to endure nearly a week and half for redemption, as well as a whole Sunday of non-Cowboy football -- that I watch, but in protest!
A lot of this board will say it doesn't effect them, that it's "just a game," yet the posts after a loss clearly point to the contrary
And just to amswer your OP, somewhere between 4 and 5