Eva Longoria -- Hillary Clinton For PRESIDENT ... If She Runs

Hillary Clinton is already building a pretty impressive list of celebrity backers ... 'cause Eva Longoria just told us HC can count on her support if/when she decides to run for President in 2016.

It ain't too surprising, considering Longoria is a die-hard democrat who even gave a speech at the 2012 Democratic National Convention.

Eva joins a ton of Hollywood stars who are already on-board the Clinton Express ... including Lionel Richie, Chris Rock and Barbra Streisand.

Of course, Hillary hasn't officially announced her plans yet ... but at this point, does she even have to?