U.S. Senate candidate Tim Kaine believes gay couples should be able to adopt if a judge deems it in the best interest of the child, he told the Washington Post in a recent interview.

“I think the best interest of the child is a pretty hard standard to argue with and I think that ought to be the standard,’’ said Kaine, the former governor who is now a candidate in the Democratic Senate primary.

Then Democratic National Committee Chairman Tim Kaine attends a St. Patrick's Day reception at the White House in Washington, March 17, 2011. (JONATHAN ERNST/REUTERS)

“No couples in Virginia can adopt other than a married couple -- that’s the right policy,’’ Kaine said in 2005 during his successful campaign for governor. “Gay individuals should be able to adopt.”

Kaine’s staff told the Post following the recent interview that his stance had shifted as he became increasingly convinced that the best interest of the child was all that mattered.

Virginia is one of 34 states where only single men and women and married couples can adopt, according to the American Academy of Adoption Attorneys.

Fifty-five percent of Virginians say gay couples should be able to legally adopt children, according to a recent Washington Post poll.

“If the judge determines that’s the best interests of the child I think that’s fine,’’ Kaine said. “I don’t think we should be putting artificial barriers in front of the judges who are sitting there with the family.”

The issue has been in the news recently, as the State Board of Social Services voted to continue a practice that some say allows faith-based organizations in Virginia to discriminate in adoptions.

Kaine’s administration proposed changing the regulations in November 2009, less than two months before he left the governor’s mansion to become the full-time chairman of the Democratic National Committee.

The proposed regulations, part of a massive overhaul of adoption rules, would have added protections on the basis of sexual orientation, gender, age, religion, political beliefs, disability and family status. The current rules follow federal law banning discrimination based on national origin, race and color.

Kaine said it was “very unfortunate” that the board voted the way it did after receiving advice from Attorney General Ken Cuccinelli II (R) and Social Services Commissioner Martin Brown, an appointee of Kaine’s successor, Gov. Robert F. McDonnell’s (R). All three opposed the proposed changes.

“I definitely don’t think the placement agency should discriminate and I think their rolling back on that regulation was bad,’’ he said.