Pikachu is by far one of the most iconic creations to ever grace this realm. Truly, Pikachu has made an impact that is quite possibly greater than that of any public official ever in office. I would vote for Pikachu, given the opportunity.
In generation 4, during the release of Diamond and Pearl, Pikachu gained a gender difference. Female Pikachu were given a heart-shaped tail tip. This Pikachu in particular is my favorite! Hearts are adorable, and even moreso when associated with Pokemon!
Check out my collection of female Pikachu items! While I do not consider myself a Pikachu collector, it's difficult not to pick up a few things here and there.