Here's an Obama bumper sticker for Clinton supporters. You may dream of Hillary Clinton, but the time has come to vote for Barack Obama. Make a nod of respect to one while acting in favor of the other.
Finally. This is perfect for all the Clinton supporters who didn't see their top choice get picked but still want to support the best candidate out there. Although we all love Hilary, it'd be silly to support McCain over Obama because their politics are completely backwards. This is a great way to show your support for both!