I agree with him on some things, and disagree with him on others.
But I hardly see his campaign as a joke. Lot's of people oppose Trump. That is a personal decision for each of us to make. I differ in opinion to those that oppose Trump and supported and voted for Trump. There were more than a few Republicans that opposed Trump.
Mostly a publicity stun as he runs as an independent (like his POTUS run) which means he has zero chance of winning. He is smart, he knows that, so it allows him to throw punches without any risk of every having responsibility to do something.
If he was serious he would challenge Lee in the Republican Primary or run in the Democratic one.