In a dramatic shift, Maryland voters overwhelmingly would vote to uphold a law allowing same-sex marriage, according to a survey released Thursday by Public Policy Polling.

Fifty-seven percent of likely voters would vote to uphold the law allowing same-sex marriage, while 37 percent would not, representing a 12-point shift from an identical survey in early March. Fifty-two percent think gay marriage should be recognized, while 39 percent do not. Both polls were commissioned for Marylanders for Marriage Equality.

Maryland passed a gay marriage law, but it doesn't take effect until January 1, 2013. Opponents of the law are seeking to get 55,736 signatures to force a referendum on it by June 30, which is likely to happen. Maine and Minnesota will vote on gay marriage in November.

The poll notes that the shift can be explained "almost entirely" by a change in black voters' attitudes. Previously, 56 percent said they would vote against the new law, with 39 percent saying they would vote for uphold it. Now, 55 percent say they will vote for the law and 36 percent are opposed.

President Barack Obama came out for gay marriage between the polls, amid rising support for same-sex unions.

A Washington Post/ABC poll also showed that black public opinion shifted after Obama's announcement, with 59 percent of blacks saying they backed same-sex marriage, an 18-point shift compared to polls leading up to the survey. PPP also released a poll showing an 11-point jump in North Carolina favor for gay marriage among black voters following the passage of Amendment One, which banned gay marriage, domestic partnerships and civil unions.

However, there is a note of caution -- pro-gay marriage votes have fared poorly at the ballot box, with 31 states passing same-sex marriage bans since 1998, as recently as North Carolina earlier in May. (Arizona rejected a more expansive ban of gay marriage and domestic partnerships in 2006, but passed a narrower version in 2008.)

Here are some reactions to Obama's gay marriage announcement:

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  • Mitt Romney

    "I believe marriage is a relationship between a man and a woman," Mitt Romney said.

  • Kyrsten Sinema

  • Daniel O'Donnell

  • Kirsten Gillibrand

  • Jeff Merkley

  • Elizabeth Warren

  • Michael Bloomberg

    "This is a major turning point in the history of American civil rights," said New York City mayor Michael Bloomberg. "No American president has ever supported a major expansion of civil rights that has not ultimately been adopted by the American people - and I have no doubt that this will be no exception. The march of freedom that has sustained our country since the Revolution of 1776 continues, and no matter what setbacks may occur in a given state, freedom will triumph over fear and equality will prevail over exclusion. Today's announcement is a testament to the President's convictions, and it builds on the courageous stands that so many Americans have taken over the years on behalf of equal rights for gay and lesbian Americans, stretching back to the Stonewall Inn in Greenwich Village."

  • Jerrold Nadler

    "I applaud President Obama for announcing his support for marriage equality today," said Rep. Jerrold Nadler (D-N.Y.) "For the first time in this nation's history, a sitting president has shown the courage and leadership to stand up for all American families by pledging to support the fundamental right of every person to marry the person they love, and to have that marriage fully respected. I commend President Obama for this brave and honest step. Those who seek to politicize civil rights for personal or political gain will certainly attack him, but the course toward marriage equality and justice is the correct and inevitable path."

  • Brad Lander

  • Fred Karger

    "I'm thrilled!" longshot GOP presidential candidate Fred Karger told HuffPost, referring to Obama's embrace of marriage equality. Karger is the first openly gay Republican or Democrat to run for president. "The Karger pressure has worked," he joked. "Particularly after the defeat in North Carolina, we welcome him to the full equality position."

  • Vince Gray

  • Martin O'Malley

  • Sen. Jeanne Shaheen

  • Barack Obama

  • Mark Udall

  • Senator Chris Coons

  • Rep.George Miller

  • Jim Himes

  • Nancy Pelosi

  • Nita Lowey

    "I have been blessed to have a long and happy marriage. I strongly believe all Americans deserve that same opportunity," said Rep. Nita Lowey (D-N.Y.)

  • Antonio Villaraigosa

  • Jackie Speier

  • Michael Steele

  • Dennis Kucinich

  • John Brunner

  • Cory Booker

  • Chris Gregoire

  • Fred Karger

  • Ted Strickland

  • Jared Polis

  • Reince Priebus

    "While President Obama has played politics on this issue, the Republican Party and our presumptive nominee Mitt Romney have been clear. We support maintaining marriage between one man and one woman and would oppose any attempts to change that," said RNC Chairman Reince Priebus.

  • Debbie Wasserman Schultz

  • Chellie Pingree

  • Christine C. Quinn

  • Mike Huckabee

    "Barack Obama just announced he supports same-sex marriage," Mike Huckabee wrote in a fundraising appeal to supporters. "Nancy Pelosi immediately jumped on the announcement and emailed Democrat activists nationwide promising to continue their fight. This is going to be a defining issue this election. Obama, Pelosi and the Democrats have been a complete failure on economic issues so now they are going to focus on issues that will rile up their base. Well, Mr. President it's going to rile up our folks also. Men and women who support traditional marriage."

  • Rep. Bill Taylor

  • Deval Patrick

  • Frank Lautenberg

    "President Obama's support for marriage equality marks an important moment for civil rights in America," said Senator Frank R. Lautenberg (D-NJ), who co-sponsored legislation that would repeal the Defense of Marriage Act (DOMA). "We simply can not treat same sex couples as second-class citizens in our country. Marriage equality is one of the most significant civil rights battles of our time and is critical to guaranteeing the equal protection under the law promised to every American in the Constitution. The President's support for marriage equality should inspire Congress, Governors and state legislatures to advance civil rights for all Americans."

  • Allen West

  • Ann McLane Kuster

  • Sen. Patrick Leahy

  • Peter Welch

    "This is an historic moment and I applaud the President for his decision and courage," Rep. Peter Welch (D-Vt.) said. "One of the greatest and most liberating human emotions is acceptance. And what the President did today was accept that the quality of love two people share is more important than their gender. The President's decision required him look within and engage his heart. It is truly wonderful and welcome news."

  • Senator Patty Murray

  • Steve Rothman

    "As an early and strong proponent of Marriage Equality, I am very happy that President Obama has made this announcement," said Rep. Steve Rothman (D-N.J.) "Marriage Equality is a matter of basic human rights and all of America's same-sex families are now closer to having their unions recognized by our government. This is an important step in our country's march toward achieving true justice and equality for all."

  • Chuck Schumer

  • JackieForNH

  • Howard Dean

    "President Obama's public support for marriage equality is an historic affirmation of the fundamental American value of equal rights for all," said Howard Dean. "Having signed the nation's first law allowing Civil Unions as Governor of Vermont, I'm also proud to see our president affirm the belief that I and so many other Americans hold: loving and committed couples should have the same benefits that are extended through marriage. Marriage equality is a right and a benefit to all families."

  • Mike Quigley

  • Senator Ben Cardin

  • Sen. Barbara Boxer

  • Senator Dick Durbin

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