Personally, I like my Hobbits "Hobbity" and Frodo (while most definately a most admirable Hobbit) is, by the end, rather too "unwordly" to get my vote. Perhaps that's the reason for his relatively poor showing in the poll (I'm sure that he would top many others).
Of the "Fellowship Hobbits", I would have voted for Pippin, for many of the reasons that
Lyta so eloquently stated. His innocence, sense of humour and curiosity are appealing and his transition from "young innocent abroad" to Gondorian warrior is a great aspect of the story.
But my first introduction to Tolkien was courtesy of Bilbo, when I first read The Hobbit many many years ago, and I probably identify most with him of all the characters in either the Hobbit or LotR (with the possible exception of Butterbur

). So its Bilbo who gest my vote.