The political connotations of marijuana have changed significantly over the years. In the 1970s and 1980s, most politicians in the U.S.—Democrat and Republican alike—rallied against the drug. The famous "War on Drugs" began following a speech by Richard Nixon in the early 1970s and continued as a federal government initiative of some form or another for decades. While the "War" was focused on psychoactive drugs of all kinds, marijuana was commonly considered to be a "gateway" drug which could lead people down the path toward more serious (and lethal) addictions.

Looking ahead several decades, there are many signs that the general public consensus on marijuana has shifted considerably. Dozens of states across the U.S. have moved to legalize marijuana growth, sales, and usage in one or more circumstances. While the move toward legalization tended to begin in states with a traditionally liberal political lean, there are now many traditionally conservative states that have adopted the policy as well. Further, one need only take a look at the Democratic candidates for President heading into the 2020 general election to recognize immediately just how the political implications of marijuana in particular have changed as well.

Below, we'll explore the positions on legal cannabis of many of the top Democratic contenders for President in 2020.

Cory Booker

Democratic Senator from New Jersey Cory Booker has made marijuana reform a pillar of his political life. In 2018, his home state passed legislation indicating a move toward legalization, and before that, Booker wrote the Marijuana Justice Act aimed at radically revamping cannabis legislation across the country. This Act would not only legalize the substance on a federal level, but also expunge convictions for many individuals convicted of marijuana-based offenses and also punish states for the practice of unfairly targeting minority populations in the War on Drugs. The Act did not make it out of the Senate, but it nonetheless has come to represent a test of sorts for Democrats when it comes to marijuana reform.

Pete Buttigieg

One of the few contenders for the Presidency without Congressional experience, Pete Buttigieg is the mayor of South Bend, Indiana. While Buttigieg has only recently risen to national prominence and has not spoken at length about marijuana legalization, his own political leanings seem dramatically more progressive than his conservative home state. Indiana has not legalized marijuana in any case.

Julián Castro

Julián Castro, the Secretary of Housing and Urban Development in Barack Obama's administration, is a politician from Florida. Florida has moved to legalize medical marijuana but not recreational usage. Castro's support for legalization has been similar to that of his home state; he has advocated for legalization of some kind and has made social media posts suggesting that the federal government should not prioritize crimes related to recreational marijuana usage. However, because of Castro's background, he does not have a Congressional voting record on cannabis, which makes it a bit tougher to say how he might approach the drug as President.

Tulsi Gabbard

Hawaiian Congresswoman Tulsi Gabbard is one of the more polarizing figures in the 2020 Democratic field. She holds views contrary to many of the traditional party lines, which tends to either draw ire from other Democrats or speculation that she could be an important bridge to centrists across the country in a general election. When it comes to marijuana legalization, though, Gabbard has a strongly liberal record. She not only sponsored a bill aimed at encouraging state legalization but has also called for the federal decriminalization of the drug as well.

Kirsten Gillibrand

Coming from New York, Senator Kirsten Gillibrand's record on legalization is perhaps unsurprising: she has long been in support of legalization. Gillibrand has a strongly liberal voting record overall and has also signed on to the Marijuana Justice Act, among other important pieces of marijuana reform legislation.

Although Gillibrand began her career as a conservative, she has shifted hard to the left on most policies throughout her time in the public eye. It's likely that she would maintain these perspectives going forward, even into the Presidency.

Kamala Harris

California Senator Kamala Harris has had a complex relationship with marijuana in the past. Previously, the former attorney general did not seem to be in support of legalization of recreational marijuana. However, in more recent years, she has written that she now advocates for not only legalization, but also for the clearing of criminal records for those convicted of marijuana offenses, so long as they were non-violent ones. What's more, Harris has also admitted to smoking (and inhaling) marijuana in the past.

Amy Klobuchar

Amy Klobuchar, a U.S. Senator from Minnesota, is traditionally viewed as one of the more centrally-leaning Democratic contenders for President heading into the 2020 race. Accordingly, she has a somewhat hard-to-parse view on marijuana legalization. While Klobuchar has signed on to the STATES Act, which aims to grant protection from federal intervention to individual states that have legalized marijuana, she has not signed on to the Marijuana Justice Act. The latter Act would declassify marijuana as a schedule 1 drug per the Federal Controlled Substances Act.

It appears likely that a Klobuchar presidency would not hinder the efforts toward legalization of marijuana among individual states. On the other hand, it may be unlikely that federal legalization would take place with Klobuchar in office as well.

Beto O'Rourke

One of the more recent entrants into the Democratic field for 2020 is Beto O'Rourke, a Democratic Congressman from Texas who first rose to national prominence in his bid to unseat Senator Ted Cruz in 2018. Unlike many of the other candidates on this list, O'Rourke's home state of Texas has traditionally been strongly opposed to the legalization of marijuana. The state allows medical marijuana usage in only rare circumstances thanks to the 2015 Compassionate Use Act.

O'Rourke has adopted a fairly open position on marijuana reform, having voted for multiple pieces of legislation aimed at increasing medical marijuana access and protecting individual states from federal intervention related to marijuana legislation. Around the same time as the announcement of his candidacy, O'Rourke also called for the legalization of marijuana at the federal level, alongside criminal justice reform related to cannabis laws. This suggests that an O'Rourke presidency might lead to sweeping national changes.

Bernie Sanders

One of the top contenders for the Democratic nomination in 2020 is Vermont Senator Bernie Sanders. Sanders was a leading candidate in the 2016 race and enjoys tremendous momentum and recognition heading into the upcoming election as well. Sanders' home state of Vermont moved to legalize recreational marijuana in 2019 through a vote in the state legislature, the first state to make such a move separate from a referendum.

Across Sanders' long and storied political career, he has frequently made efforts to reform the nation's marijuana laws. In 1995, for example, he acted as co-sponsor of a bill in the House to authorize medical marijuana treatments in certain serious cases. He has signed on to the Marijuana Justice Act, indicating his support for the de-scheduling of cannabis.

Beyond his efforts to change marijuana laws, Sanders has also worked to reform banking practices as well. One effect of such reform would be for legal marijuana businesses to have easier access to business accounts. All of this suggests that a Sanders presidency would be a boon to legal cannabis advocates across the country.

Elizabeth Warren

Elizabeth Warren, a Senator from Massachusetts, calls one of the most progressive and marijuana-friendly states in the country home. Given that, it makes sense that Warren has been a strong proponent of marijuana legalization for years. Massachusetts legalized recreational cannabis usage in 2016, with cannabis sales becoming available in late 2018.

Warren partnered with Republican Senator Cory Gardner of Colorado to sponsor the bi-partisan STATES Act, which aims to protect individual states from federal intervention when it comes to legalization decisions. Warren has also supported the Marijuana Justice Act and other drug reform bills as well. Like Bernie Sanders, Warren has also voiced support for banking reform related to cannabis to remove industry barriers for new businesses as well.

Andrew Yang

With a background in law and tech, New York politician Andrew Yang is one of the least recognizable faces among a large pool of Democratic Presidential contenders. Yang represents a state that has already moved to legalize medical marijuana and which will likely legalize recreational usage in the future as well.

Yang has adopted a pro-legalization stance, going so far as to refer to the criminalization of marijuana as "stupid and racist." Not only does he support full legalization, he also has expressed an interest in pardoning individuals convicted of non-violent marijuana-based offenses in the past.