A new Gallup poll released yesterday shows that a record-high of 50% of Americans believe the use of marijuana should be made legal. That’s up from 46% just one year ago. This is the first time we've hit the 50% mark on this highly respected annual survey, so this is significant. Even the folks at Gallup seem to have a sense something historic is happening. As they noted in the release accompanying the survey results, “If this current trend on legalizing marijuana continues, pressure may build to…