Dustin Lance Black Mulls Obama Fundraiser After Shift on Gay Marriage (Exclusive)

"Milk" screenwriter Dustin Lance Black had publicly threatened to withhold his vote. Now he's contemplating co-hosting a Los Angeles fundraiser 

Dustin Lance Black went on Thursday from fierce critic of Barack Obama to full throttled supporter after the president shifted his position on gay marriage — and he's ready to open his checkbook.

Getty ImagesSo angered by Obama’s lack of movement on marriage equality, the Oscar-winning "Milk" screenwriter had publicly suggested that he might sit out this presidential race.

But because the president spoke out in favor of same-sex marriage on Wednesday, Black told TheWrap that he is considering co-hosting a Los Angeles fundraiser on June 6 geared toward the lesbian, gay, bisexual and transgender (LGBT) community.

“I am moving from a position of little enthusiasm to a position of strong support, and that means you will see me contributing financially and repeating my efforts of 2008 by knocking on doors in states where he wants me to knock on doors,” Black said. “When you ask for something big and you get it, you have to show your gratitude.”

Also read: President Obama Supports Gay Marriage on ABC News

That’s a big change from last month when Black wrote an opinion piece in the Hollywood Reporter that criticized Obama and his Republican opponent Mitt Romney on their attitude toward gay rights and urged members of the gay community to consider withholding their vote if the president did not back same sex marriage.

At the time, Obama supported civil unions for same sex partners, but said his position on gay marriage was "evolving." That wasn't good enough for Black. 

Getty Images“Romney being elected would be devastating for the gay community, I’m not politically naive, but I also think we have to be united in our resolve to get full equality,” Black said. “The greatest power we have is our vote, so last April I considered reserving my vote. In my heart, I never wanted to do that. I was just hoping he would do the right thing.”

Those hopes were realized, Black said, after Obama voiced his support for same-sex marriage in an exclusive interview with ABC News' Robin Roberts. 

Also read: Obama's Hollywood Heavyweights: Who's Who and How Much

“I’ve just concluded that for me personally it is important for me to go ahead and affirm that I think same sex couples should be able to get married,” Obama told Roberts.

Black said he was touched by the president’s statement of support and in particular the way that he traced his own evolution on the issue.

The screenwriter added that the president’s statement, coming as it did on the heels of a gay marriage ban in North Carolina, will send a powerful statement to lesbian, gay, bisexual and transgender teenagers.

“I think it was life saving,” Black said. “The day before, North Carolina sent out a negative message to young LGBT teens that the government does not value you, and it does not respect you, so I think it did so much to salvage their wounded self-esteem. I know it saved lives.”

The statement marked the first time that a sitting U.S. president has endorsed full marriage rights for gay couples, but politically it might prove detrimental to Obama’s re-election chances. Some analysts have speculated that the president’s support for the issue could backfire in more conservative swing states like North Carolina that he won in the previous presidential contest.

Black believes the gay community now owes it to the president to help ensure that his support for marriage equality does not become a political liability.

“If that happens, we as the equality minded community have failed him,” Black said. “Our responsibility is to give him the support he needs and to do the hard work to make sure this is a winning issue even in swing states.”

“We might have a harder time in North Carolina, but we can make this a winning issue in Virginia.  We know how to win, we know how to change minds,” he added. “Our job is to personalize our struggle and dispel the myths about gays and lesbians.”