Support for gay marriage has increased in all 50 states, and 20 states and the District of Colombia will have majority support by the end of 2014.

Those are the conclusions of a report released last week by the UCLA's School of Law's Williams Institute.

According to the report, titled Public Support for Marriage for Same-Sex Couples by State, 12 states and the District of Colombia had support for marriage equality at or above 50% by the end of 2012.

An additional 13 states currently are within 5 percentage points of majority support. And support over the last eight years has increased in all 50 states, with an average increase of 13.6%.

“The results indicate that all of the states have increased in their approval of marriage recognition for same-sex couples since 2004,” the report's authors wrote. “In 2004, there was not a single state that had a majority in favor of same-sex marriage.”

States with the lowest levels of support include Alabama, Arkansas, Kentucky, Louisiana, Mississippi, Oklahoma, South Carolina, Tennessee, Texas and West Virginia.

Additionally, the authors estimate that all 50 states will reach majority support in slightly less than 20 years.