Here is a short list of things that, according to Gallup, are less popular with Americans than the idea of legalizing pot:Congress. The U.S. Supreme Court. The president.In a sweeping cultural shift, comparable perhaps to Americans’ quickening support of same-sex marriage, a majority of Americans now favor legalizing marijuana use, according to a Gallup poll released Tuesday. The survey showed that 58 percent of 1,028 respondents supported legalization, with 39 percent against.That’s a drop for the naysayers from just three years ago, when 50 percent of respondents opposed legalization — a number already riding a long plummet from a high of 73 percent in the 1990s.Gallup credited much of the surge to political independents, whose support for legalization jumped from 50 percent to 62 percent in less than a year.And what a year it has been for marijuana advocates: Last November, voters in Colorado and Washington easily passed ballot initiatives — 55 percent to 45 percent in each state — to legalize the possession and sale of marijuana. In Colorado, the legalization measure got more votes than President Barack Obama, who won the state.After the victory, advocates and politicians alike were unsure how federal law enforcement authorities would react to state laws that contradict federal laws that prohibit marijuana use and list it as a controlled substance.Those tensions eased after the Justice Department announced in August that federal officials would not interfere with voter-approved laws that legalized recreational marijuana use, as long as the state laws were strictly regulated.