I'm genuinely confused why you're not paying respect to anything that was actually said. You are either ascribing your own meanings to the post or you cannot read properly. I will paste the post here again:

The only bracket Clinton won here in the Shire was over 65. Stop simplifying or assuming or whatever it is you're doing.

Here is my post, again:

Isn't this the case because Bernie's voter demographic is almost all people from 18-25? I can only imagine every Republican nominee (except maybe Trump) has a much older demographic. Certainly not a demographic that visits websites routinely. They'd probably rather have something mailed to them.

What meaning are you ascribing to the following post that includes Bernie Sanders?

The only bracket Clinton won here in the Shire was over 65. Stop simplifying or assuming or whatever it is you're doing.

So, the two key points of this declarative statement involve Hilary Clinton winning voters over 65. Conversely, this post only saying, in regards to Bernie Sanders, that he won every other demographic that was not over 65 (including the 18-25 demographic I explicitly noted), but it makes no reference to the distribution.

So, let's move on to what you are trying to say:

You made a claim: that Sanders was capable of capturing only the 18-25 demographic.

Maybe you should go back and re-read my post, or you should reconsider how loosely you use the word "only."

Isn't this the case because Bernie's voter demographic is almost all people from 18-25? [...]

Let's see about this part:

[...]Allgoodonesaretaken9 pointed out that in at least one instance, a demographic that was not 18-25 went for Sanders.

I'm again going to say either you're ascribing something that is not explicitly stated here or you cannot read, and I will re-paste the post you are referring to here:

The only bracket Clinton won here in the Shire was over 65. Stop simplifying or assuming or whatever it is you're doing.