An outgrowth of an already very effective organization:

As gay people around the country reveled on Sunday in the historic Senate vote to repeal “don’t ask, don’t tell,” a liberal media watchdog group said it planned to announce on Monday that it was setting up a “communications war room for gay equality” in an effort to win the movement’s next and biggest battle: for a right to same-sex marriage.

The new group, Equality Matters, grew out of Media Matters, an organization backed by wealthy liberal donors — including prominent gay philanthropists — that has staked its claim in Washington punditry with aggressive attacks on Fox News and conservative commentators like Rush Limbaugh and Glenn Beck.

It will be run by Richard Socarides, a former domestic policy adviser to President Bill Clinton who has been deeply critical of President Obama’s record on gay rights. A well-known gay journalist, Kerry Eleveld, the Washington correspondent for The Advocate, will leave that magazine in January to edit the new group’s Web site, equalitymatters.org, which is to go online Monday morning.

Wherever Kerry is, she’s an asset, so we’ll be looking forward to having Equality Matters on the front lines in Washington. For now, check out the site here.