Legislators in more than a dozen states have introduced measures to loosen laws restricting access to or criminalizing marijuana, a rush of legislative activity that supporters hope reflects a newfound willingness by public officials to embrace a trend toward legalization. The gamut covered by measures introduced in the early days of legislative sessions underscores the patchwork approach to marijuana by states across the country — and the possibility that the different ways states treat marijuana could come to a head at the federal Justice Department, where Trump’s nominee to become attorney general is a staunch opponent of legal pot.