I'm not sure the WH even reads them (unless you're a donor). The best way is to contact your district Rep and Senator... just remember it will likely get you put on a "list." I contacted my Rep about immigration and he sent me an email about cloture in the Senate being the most important issue... I sent him one back calling him a feckless cunt. Tom Cotton sends you a stock reply "Thanks for contacting me, blah, blah, blah. John Boozman is really good, he always sends a heartfelt reply and is concerned about the issues and he listens.

To get a WH response it will take volume- thousands of emails. I send them in hopes that it may make a difference and it has... I'm on a FBI list now lol.