As you may know, there is a lot of things how you can in real propagate your team. You can invest into a billboards, websites, leaflets, newspapers, TV, pictures on a tickets, etc etc (from very little things to a huge)
These things do your PR, however he needs sometimes an extra budget and if your decision is on a right time, you can expect a well good feedback, which more than covers your invests.
I imagine that I can invest before expected winning series one-shot (example) 1000 000 and if people starting to come, their's volume, volume of decided new ticket holders and merchandise revenue (etc) grows as winnings are succesfull.. however the influence should be only temporary, because there are lot of people which cannot resist against a hype propagations, but they aren't loyal or enjoyed forever
of course if your winning plans fails, fails even your investments
while there are teams which are winning all the time - this influence would not so affect them.. while they can make some little difference
you can even propagate only one match once, twice per season (or more?) and depends on quality of your oponent what will you get
you can invest into a things for a season in overall
everything is on your decision - you have any plan, so you can invest, but if your expectations fail, you will lose some cut from the campaign investment
or something different?