There's no need to wonder why all of the remaining presidential candidates support some kind of reform of the federal government's prohibition on marijuana. The public's appetite for change is growing steadily according to a new poll conducted by the Associated Press and the University of Chicago. 61 percent of Americans support the legalization of cannabis - up from 58 percent in a similar poll conducted last fall.

Support for legalization has been climbing steadily for 45 years now, from a low of 12 percent in 1970.

Tom Angell, founder of the Marijuana Majority, says Americans are obviously ready for the federal government to catch up to reforms already taking place in states that have legalized marijuana for recreation and medical use.

"This is yet another demonstration of just how ready Americans are for the end of marijuana prohibition," said Angell. "The growing level of support for legalization that we see in poll after poll is exactly why we're now in a situation -- for the first time in history -- where every major presidential candidate in both parties has pledged to let states set their own marijuana laws without federal interference."

The main survey question was direct: "Do you think the use of marijuana should be made legal, or not" 61 percent said yes, 39 percent said no.

There were follow questions, however, that revealed the various ways in which the respondents thought marijuana should be legalized. 33 percent said it should be legal with no restrictions. 43 percent said it there should be restrictions on purchase amounts, and 24 percent said it should legal only for people with a medical prescription .

Black, hispanic and poor Americans prosecuted more frequently

The poll also revealed the attitudes of Americans toward the treatment of black, hispanic and low-income people. The survey asked, "How likely do you think substance users in each of the following groups are to be convicted of drug possession?"

66 percent of respondents said black Americans were likely to be convicted of possession, followed by low-income earners (63 percent) and hispanic Americans (55 percent). By contrast, only 30 percent of poll respondents thought white Americans were likely to be convicted of possession.

Many politicians and activists have called for the end of the racially-biased persecution of black and Americans for marijuana-related offences, most notably Bernie Sanders in the ongoing campaign for the presidency.

h/t The Washington Post / Banner Image: R. Gino Santa Maria / Shutterstock.com