New Jersey
If there's one state that stands head and shoulders above the rest in terms of likelihood to legalize adult-use marijuana in 2020, my vote goes to New Jersey.
On Dec. 16, the Garden State's Senate and Assembly voted -- 24-16 and 49-24, respectively -- in favor of putting a constitutional amendment on the November ballot that would legalize adult-use pot. The measure, which is pretty much consistent with what other states have previously passed, would allow for persons 21 or older to buy cannabis products, and would give the state and municipalities (should they choose) the right to impose a tax on marijuana products.
Aside from the fact that two-thirds of Americans support the idea of legalizing recreational marijuana, according to Gallup's October 2019 poll, New Jersey was within reach of waving the green flag on adult-use weed in March. Regulators were in favor of legalizing the drug, and had agreed upon an appropriate tax.
The monkey wrench came when certain lawmakers wanted to see an expungement clause introduced for folks previously convicted of cannabis use or possession. On-the-fence New Jersey lawmakers wouldn't support this aspect of the proposal, and momentum for legalization stalled. With the Garden State's ballot measure specifically focused on consumption and not expungement, it looks to have a very good chance to pass.