It is worth keeping in mind that people in politics are not only interested in what their constituents believe, but in how strongly they believe it.  They generally give more weight to a written letter, wherein an envelope had to be made, and a stamp affixed, than they do to e-mails, faxes or phone calls.

Your Address

Your City, State  Zip

Date

The Honorable <Name>

United States Senate                          or            United States House of Representatives

<Locate address>                                              <Locate address>

Washington, D.C.  20510                                    Washington, D.C.  20515

Dear Senator/Representative <Surname>:

I am writing to express my support for the Bush administration's policy towards Iraq.

I believe that Saddam Hussein presents a clear threat to the security of Iraqi citizens, the middle east and the rest of the world.  I also believe that he has been given sufficient opportunity to comply with United Nations resolutions regarding his armaments, and that he has no intention of substantively cooperating with the requirement that he destroy all proscribed weapons.

I urge you, should further opportunity arise, to vote in favor of military action, with or without further United Nations support.

Sincerely,

<Your Name>