I voted on all 9 vote links just a few minutes ago, and my vote bonus didn't increase. All 9 went through and showed the "You Successfully Voted On ___" message and gave me the rupees and tokens, but there was no mention of the vote bonus going up. I was at 42 and I should have gotten a message about going to 43.
as said the message is there. your first vote likely was a little too early, but each vote reduces the time needed for your next vote bonus increase, which then pushed your 2nd vote into range.