The other day I reported that top Obama campaign officials have held discussions with leading Dems over the possibility that the president will come out for gay marriage before the election. There’s a simmering controversy over whether marriage equality language will be included in the party platform at the convention, which could increase pressure on Obama to complete his evolution on the issue.

Proponents of marriage equality contend that the move could actually be good politics for Obama. It could juice up fundraising, excite core Dem constituencies well beyond gay and lesbian voters, help recapture the historic aura of 2008, and trigger an outcry from the right that could force the GOP back into a culture war footing.

But the Chicago Tribune’s Michael Memoli gets political advisers to offer some detail on why they think it might be bad politics for the President:

Some political advisors argue that an election-year epiphany on the issue would be seen as simple political opportunism at a time Obama’s campaign is eager to highlight principled decisiveness. And gay marriage remains controversial among at least one major constituency the president needs: African American voters. Pastors of black churches, for example, have led the effort for a referendum in Maryland to overturn the state’s new law allowing same-sex marriage.

The sourcing on this is a bit murky, but it’s worth considering, on the chance that it accurately represents the Obama inner circle’s thinking. On the latter claim, it seems unlikely that Obama coming out for gay marriage would have an appreciable impact on African American support for the reelection of the nation’s first black president, but I suppose anything’s possible.

The argument that coming out for gay marriage in an election year would smack of political opportunism is more interesting. Given Obama’s record so far on gay rights, few gay advocates believe that Obama genuinely opposes gay marriage. The result is that his current stance already seems at least as politically opportunistic as coming out for marriage equality would, if not more so. Indeed, this gets to the heart of what has been the problem all along: Each time Obama does something positive on gay rights, that only reinforces the sense that he does support full equality for gay and lesbian Americans — including marriage equality — and increases impatience among them for him to say so already.

If anything, the fact that either stance risks coming across as political opportunism only serves as a reminder that his position on gay marriage has essentially been untenable ever since he declared that he’s “evolving.”