I think the question is which is more important to you, the platform or the individual fundraiser? The site will gain attention through each "poll," however, marketing the site alone may not ensure the success of the different polls. But if it were me doing it, I'd market both. The truth is they are one in the same. If people don't care about what is being challenged on the site, you have no website. Vice versus, they won't care about the website, if you don't have exciting challenges.