2004 Chevy Monte Carlo car won't start

Electrical problem
2004 Chevy Monte Carlo Front Wheel Drive Automatic 64 k miles

I have been driving around with no problems.
But after I came home and turned off my car, and went to turn it on later, nothing!
My lights looked fine, but I only heard 'clicks'.

Later, I tried again, but this time my lights did look dim.

I realize that it could be my battery, but could it be something else, such as the starter?
Thanks