Not in my experience. It's somewhat different. Just to reiterate it isn't like voting in an election.
You are a member of the Union.
My Union is as centre ground as you can get and isn't even affiliated with the Labour Party. I couldn't even tell you who was in charge now.
What I do know...
It's odd but at the same time it's not a political party - it's a Union.
I'm a member of a Union but have never bothered to vote for the leader. I have however voted for a number of other things because as a member of a Union you get to vote on everything :)
The other 87.8% are far from...