I'm running for 10th grade cl president and one of my opponents is playing dirty... what do I do?

A few days ago i hung up around 70 posters around my school for my campaign and a bunch have been ripped down and two have been drawn on. One of the people I'm running against used to be one of my good friends until this school year when he started hanging out with the school weirdos. Well this morning one of my friends told me something Alec (the dude I'm running against) said about me. He said "Hey, don't vote for Olivia, she's Hitler and I'm Obama!" Okay i was extremly offended by that because he called me Hitler. The other thing is, he a major Republican and cried when Obama won. He's also the one ripping down my posters. This morning when I got to school I talked to the person in charge of student gov. and she said that if he does anything like this again then he'll be taken out of the running. What can I do to make sure he gets caught? Because even if I don't win, I don't want someone like this representing my school! Oh my friend who he said that to is also offended because Alec is racist and admitted that because my friend is black, he thought he would be an Obama fan.