American Pika?

[jamesjr934]

From the images I've been able to find of animals in my area (southern Colorado Rockies) this appears to be an American Pika. But from what I've read Pika have no visible tail. As seen poking out from under its chin this has a fluffy tail. If not a Pika, what could it be? Is it just some kind of rat (don't rats have an almost fur-less tail?)?

Thanks in advance...