In article ,
"marlinspike" wrote:

I have always been concerned with the laws of my local government;

A good thing. We forget that the people are ultimately the government
in the U.S., and that all government power proceeds from the people.
When we remain ignorant and silent we surrender our freedom.

however, I have noticed that thanks to fountain pens, I find myself
writing my local government to either support their plans or to
discuss certain laws (i.e. why they are wrong :-)

Excellent!

If the political parties want people to get out the vote,

They don't, unless they know we'll vote for them.

they ought to start
sending people fountain pens!

Now this is a great idea! Fountain pens in the schools!

My only question is this, can I legally write my local government
daily about the same issue, or is there some law against mail
harassment?

Yes and no. It depends on how many content-free form letters you want
to receive from your elected representatives:

Dear (your name here)

Thank you for taking the time to write to us with your concerns. It
is important to hear what America's citizens have to say about these
important issues. Your opinion matters to all of us in (insert
government branch here), and we will work hard to do our best for as
many of our citizens as we feasibly can in these difficult times
within the constraints of current fiscal policy and appropriations
limitations.

Please feel free to keep in touch.

Sincerely,
(signature of talking head here)