Justices of the Supreme Court, take note: according to a new Washington Post/ABC News poll released today, a full fifty percent of Americans say that regardless of their own views on marriage equality, they believe that same-sex couples' freedom to marry is a right guaranteed by the U.S. Constitution.

Since 2012, polls have consistently shown that a clear and growing majority of Americans support legal same-gender marriage, and today's poll is no exception: 56 percent of those surveyed say they are in favor of civil marriage equality. But these latest ABC/WaPo findings are significant because they show that the majority's support for marriage equality has deepened much further than merely endorsing the existence of same-sex marriage in states where it's legal, to the belief that the freedom to marry falls under the Constitution's guarantee of "equal protection of the laws."

Today's numbers confirm and reinforce the findings of an ABC/WaPo poll conducted in March, which also found 50 percent support for a constitutionally-protected right to same-sex marriage. As the Washington Post's Greg Sargent points out, majorities of both independents and moderates now believe marriage equality is a constitutional right. Only Republicans and conservatives continue to oppose it:

And once again, Republicans and conservatives are alone on this question. While 50 percent of independents and 54 percent of moderates say the Constitution's equal protection language gives gays and lesbians the legal right to marry, only 34 percent of Republicans and 29 percent of conservatives say the same.

There is also a significant generation gap on the issue: 60 percent of Americans under 40 believe marriage for gays and lesbians is a constitutional right, but just 38 percent of respondents 65 and older feel the same.

Sargent calls this a major milestone for the LGBT civil rights movement, and he's right. But what's equally significant is the message it sends to the United States Supreme Court, which -- with a slew of marriage equality cases working their way through the federal court system -- will likely have to decide the constitutionality of same-sex marriage in the next two years.

Today's numbers send a strong, unmistakable signal to the justices that America is ready for full, nationwide marriage equality. Let's hope they're paying attention.