Accounting for some tax breaks you could have gotten the lowest-end model for ~$50k, which, I think, is close enough. The price on their website starts at $52,400 (taking the tax break into account).

The Model S Performance starts at $87,400. However, this is a very special top-of-the-line car, comparable to an AMG or M model from Mercedes or BMW respectively. This is definitely not the average car or the average price.

Of course, just like its German rivals, the price does go up with some options. But if you just want a nice electric car, the options are, well, optional. (Although I wouldn't pass up the tech package if I could afford it :P.)

And it's not like the standard equipment is weak--the well-publicized gigantic touchscreen comes standard, for example.

Anyhow, basically you can get one for a bit over $50k; the price only goes up if you want a longer range and some nice options.