But you are only talking about money. Think of freedom. The President is one of the greatest slaves while he is in office. Really, almost no freedom at all.
he chose to put himself up for election and is well compensated for it, he is not a slave
as for the costs of promoting his positions. if there are 131m households in USA and if there is (demo number) $1.3b expenditure on campaigning. its only $20 per household spent on promotional materials/adverts to get 50% vote if everyone voted
its only $40 per household spent on promotional materials/adverts to get 50% vote if half of households voted
in short it only costs <$50 to win a vote