put "Dear Senator" in the TO ADDRESS field, have it routed to yourself in your address book for a file copy. Then paste the following list into the BCC ADDRESS field and each recipient will be unaware that you have blanketed them all.
chuck_grassley@grassley.senate.gov; chuck_hagel@hagel.senate.gov; comments@roth.senate.gov; connie@mack.senate.gov; conrad_burns@burns.senate.gov; craig@thomas.senate.gov; dick@durbin.senate.gov; email@murkowski.senate.gov; frank_lautenberg@lautenberg.senate.gov; info@kyl.senate.gov; jesse_helms@helms.senate.gov; jim_inhofe@inhofe.senate.gov; john_ashcroft@ashcroft.senate.gov; john_kerry@kerry.senate.gov; kit_bond@bond.senate.gov; larry_craig@craig.senate.gov; mail_grams@grams.senate.gov; mailbox@gregg.senate.gov; mailbox@rpc.senate.gov; max@baucus.senate.gov; mcollins@rnchq.org; michigan@abraham.senate.gov; olympia@snowe.senate.gov; opinion@smith.senate.gov; pat_roberts@roberts.senate.gov; sam_brownback@brownback.senate.gov; sen_dodd@dodd.senate.gov; senator.hutchinson@hutchinson.senate.gov; senatorlott@lott.senate.gov; senator@akaka.senate.gov; senator@bennett.senate.gov; senator@biden.senate.gov; senator@boxer.senate.gov; senator@breaux.senate.gov; senator@bryan.senate.gov; senator@cochran.senate.gov; senator@collins.senate.gov; senator@conrad.senate.gov; senator@dorgan.senate.gov; senator@dpm.senate.gov; senator@enzi.senate.gov; senator@feingold.senate.gov; senator@feinstein.senate.gov; senator@hutchison.senate.gov; senator@inouye.senate.gov; senator@kennedy.senate.gov; senator@landrieu.senate.gov; senator@levin.senate.gov; senator@mcconnell.senate.gov; senator@mikulski.senate.gov; senator@nickles.senate.gov; senator@rockefeller.senate.gov; senator@santorum.senate.gov; senator@sarbanes.senate.gov; senator@sessions.senate.gov; senator@shelby.senate.gov; senator@thurmond.senate.gov; senator@warner.senate.gov; senator@wyden.senate.gov; senator_bingaman@bingaman.senate.gov; senator_byrd@byrd.senate.gov; senator_chafee@chafee.senate.gov; senator_coverdell@coverdell.senate.gov; senator_dewine@dewine.senate.gov; senator_domenici@domenici.senate.gov; senator_frist@frist.senate.gov; senator_gorton@gorton.senate.gov; senator_hatch@hatch.senate.gov; senator_kohl@kohl.senate.gov; senator_leahy@leahy.senate.gov; senator_lieberman@lieberman.senate.gov; senator_lugar@lugar.senate.gov; senator_max_cleland@cleland.senate.gov; senator_mccain@mccain.senate.gov; senator_murray@murray.senate.gov; senator_reid@reid.senate.gov; senator_specter@specter.senate.gov; senator_stevens@stevens.senate.gov; senator_thompson@thompson.senate.gov; senator_torricelli@torricelli.senate.gov; senatorlott@lott.senate.gov; tim@johnson.senate.gov; tom_daschle@daschle.senate.gov; tom_harkin@harkin.senate.gov; vermont@jeffords.senate.gov
Why just send it to yer Senator when you can e-FReep them all, my FRiend...MUD