Voters deserve to know who is paying for political advertisements, Sen. Bernie Sanders and 10 other senators wrote in a letter to the Federal Election Commission. The panel is considering rule changes in the wake of the Supreme Court's decision in Citizens United v. FEC, which struck down limitations on corporate funding of political ads. The senators called on the commission to implement broad disclosure and disclaimer requirements so that voters know who is funding campaign commercials. Sanders also has proposed a constitutional amendment to overturn the ruling. Some 30 towns throughout Vermont will consider resolutions supporting a constitutional amendment on March Meeting Day.