WASHINGTON (AP) — President Barack Obama has declared his unequivocal support for gay marriage, becoming the first president to endorse the politically explosive idea.

The move injects a polarizing issue into the 2012 race for the White House.

Obama revealed his support for gay marriage in an interview with ABC News.

Obama said, "I have hesitated on gay marriage in part because I thought that civil unions would be sufficient." He added that he "was sensitive to the fact that for a lot of people the word 'marriage' was something that invokes very powerful traditions, religious beliefs and so forth."

Now, he said, "it is important for me personally to go ahead and affirm that same-sex couples should be able to get married."

He says he came to the conclusion over the course of several years of talking to family and friends.

Obama had refused to take a clear stand for months, but today's announcement cheered gay rights groups who have long urged him to support gay marriage. It also opens up a distinct area of disagreement with Mitt Romney, who opposes gay marriage.

Polling suggests the nation is evenly divided on the issue.

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