Sophia Bush Non-Voters Should Be ASHAMED

11/5/2012 7:45 AM PST

Tomorrow is the election ... and if you don't vote, you should be ASHAMED of yourself ... this according to former "One Tree Hill" star Sophia Bush.

Bush isn't shy when it comes to politics ... she's a huge Obama supporter ... and even had lunch with the President back in June.

But on her way out of The Sayers Club in L.A. this weekend, the 30-year-old actress made it clear ... she has no tolerance for people who don't exercise their constitutional right to vote.

So, we gotta ask ...