Funny that you mention these two, as Bill Watterson cited both Pogo and Krazy Kat as major influences on Calvin and Hobbes in the Tenth Anniversary Book.

BTW, if you are a fan and for some reason have not read the Tenth Anniversary Book, I strongly recommend it. Watterson's commentary throughout is awesome and really highlights the brilliance of the strip.

http://www.amazon.com/Calvin-Hobbes-Tenth-Anniversary-Book/d...