Survey results released Thursday indicate 68 percent of respondents support Collins' decision and 23 percent are opposed.
Collins, a 34-year-old free agent center, announced he is gay in a first-person Sports Illustrated story posted on magazine's website April 29. The 14-year NBA veteran finished the 2012-13 season as the Washington Wizards' center. He is the first active male athlete in a major U.S. sport to announce he is homosexual.
Collins' biggest support is among those who identified themselves as Democrats or college graduates, and people 30 years old or younger, with 81 percent of respondents in each group saying they support his decision, the Post said. Ninety percent of gay-marriage supporters said they support Collins.
Of those who identified themselves as "very conservative" politically, 45 percent said they support the decision and 47 percent oppose it. Among those identifying themselves as gay-marriage opponents, 41 percent said they support Collins' announcement and 50 percent opposed.
Results are based on a national sampling of 1,008 adults conducted May 1-5. The margin of error is 3.5 percentage points.