Updated at 8 p.m. ET
Commentators and politicians from the left and the right say Congress could take the next move now that President Obama's Justice Department has (DOMA)-- and it looks like a member of Congress from the left side of the aisle is the first to act.
Democratic Sen. Dianne Feinstein of California released a statement today saying that she intends to introduce legislation to repeal DOMA, which bars federal recognition of same-sex marriages.
"My own belief is that when two people love each other and enter the contract of marriage, the Federal government should honor that," Feinstein said. "I opposed the Defense of Marriage Act in 1996. It was the wrong law then; it is the wrong law now; and it should be repealed."
Equality Matters President Richard Socarides lauded President Obama for showing "bold leadership" on the issue and said in a statement that the decision "means that the discriminatory and harmful Defense of Marriage Act is on its last legs. The federal government is one big step closer to providing equal rights and responsibilities to millions of loving and legally married same-sex couples."
Supporters of DOMA, however, condemned the administration's decision and called on Republicans in Congress to intervene.
Tony Perkins, president of the conservative Family Research Council, called the Justice Department's decision "appalling."
"With this decision the President has thrown down the gauntlet, challenging Congress," he said in a statement. "It is incumbent upon the Republican leadership to respond by intervening to defend DOMA, or they will become complicit in the President's neglect of duty."
Maggie Gallagher, chairman of the National Organization of Marriage, called the decision a "truly shocking extra-constitutional power grab" and a "defection of duty" by the president, CBS News chief legal correspondent Jan Crawford.
"The good news is this now clears the way for the House to intervene and to get lawyers in the court room who actually want to defend the law, and not please their powerful political special interests," Gallagher said.
In an interview with CBSNews.com's Washington Unplugged today, former Arkansas Gov. Mike Huckabee said the administration's decision "may destroy [President Obama's] credibility, may destroy his campaign and candidacy, and ultimately his term in office."
So far, Republican leaders have issued statements decrying the president's decision, without any indication of whether they will intervene in the pending court cases.
House Speaker John Boehner's spokesman Michael Steel said in a statement to CBS News that Mr. Obama will have to explain to the American people why, despite a desire for lawmakers to focus on the still-struggling economy, "he thinks now is the appropriate time to stir up a controversial issue that sharply divides the nation."
Laena Fallon, a spokesperson for House Majority Leader Eric Cantor (R-Va.), similarly said it was inappropriate for the president to bring the Justice Department into a "political chess game."
"While Republicans are focused on cutting spending so that we can grow the economy and create jobs, the White House is more interested in rekindling hot button political issues to distract from the current debate over how to fund our government in the most fiscally responsible way," she said.
House Judiciary Committee Chairman Lamar Smith (R-Texas) called the administration's decision "irresponsible."
"It is a transparent attempt to shirk the Department's duty to defend the laws passed by Congress," Smith said. "This is the real politicization of the Justice Department - when the personal views of the President override the government's duty to defend the law of the land."
A spokesperson for Smith said, however, that it is up to House leadership to determine whether to intervene in court.
The conservative American Principles Project released a statement in line with other conservative groups, concluding that Republicans are now obligated to act.
"President Obama is not only refusing to defend marriage, but is unilaterally overturning the will of the people, as expressed through their Congressional representatives and affirmed by his fellow Democratic President, Bill Clinton," American Principles Project Frank Cannon said. "It now falls to Congress to demonstrate true leadership and respond to the 63 percent of American voters who in 31 states have acted to defend traditional marriage at the state level."
Joe Solmonese, president of the gay rights group the Human Rights Campaign, said that "Congressional leaders must not waste another taxpayer dollar defending this patently unconstitutional law."
"The federal government has no business picking and choosing which legal marriages they want to recognize," he said. "Instead Congress should take this opportunity to wipe the stain of marriage discrimination from our laws."
The American Civil Liberties Union, one of the groups challenging the law in court, said the Obama administration "just propelled gay rights into the 21st century."
"Our government finally recognizes what we knew 14 years ago - that the so-called 'Defense of Marriage Act' is a gross violation of the Constitution's guarantee of equal protection before the law," ACLU Executive Director Anthony Romero said. "DOMA betrays core American values of fairness, justice and dignity for all, and has no place in America. Our Constitution promises that the government will treat everyone equally. Today's announcement is a recognition that gay people, too, are promised equal treatment under the law."