Where to promote dog tumblr account?

[Carolynn]

I create a tumblr for all dog lovers and dog owners to share their lovely furry friends' photo, video, etc. I'm thinking about creating a monthly challenge (for example, dog in car, swimming, costume, holiday, etc.) once it gets famous so that people could share the joy of having a pooch to others dog lovers. But I don't know how to start gaining followers to submit theirs. Is there any web out there where I can promote my tumblr?

Here is my tumblr account:
http://shareyourpooch.tumblr.com/

[FidosCityGuide]

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