I don't think they really see their work as effecting the votes really, at least not intentionally. They're doing this for fun first and foremost, but they also like the exposure - people following them on twitter, subs on youtube, followers on DA, etc. Gives them more incentive to create more stuff when maybe if no one cared they'd have just done a couple. Travis was the Mother's Day gift, so to speak. They didn't create him thinking "we better get this out before the ballot ends instead of characters that actually have a chance". Like Edgy said, it started out as giving characters with little chance a bit of the spotlight.
If anything, the popular characters were on their backburner until fans started demanding them. I believe I've even seen them state that they were a bit hesitant in making characters that had a good shot for DLC because they'd get an official render themselves soon potentially. Only reason to do popular characters is because of fan demand and because they want to anyways. They don't recognize the invisible deadline in October as anything but the potential for a character they had planned to make having an announcement and a render, forcing them to change their plans on said character. They're not going to make a character that already has a Smash render, and I believe they're staying away from vets too for similar reasons. I recall one comment that they were at least not interested in doing Snake because he's a vet with several high quality 3D renders out there... basically, they wouldn't be doing anything "new".