"We've seen a profound cultural shift just in the last decade," Obama says in the five-minute film narrated by Glee star Jane Lynch.
The new project marks Gay Pride Month, and comes just a few weeks after Obama endorsed gay marriage following years of vacillation on the topic.
The film spotlights that decision, as well as Obama efforts on such gay and lesbian issues as hospital visitations, spousal benefits, federal appointments, and statutes against hate crimes.
If re-elected, Obama pledges to be a "strong advocate" to "preserve the gains that we've made over the last three years," and to expand gay rights in such areas as adoptions and lifting travel bans.
The campaign effort to organize lesbian, gay, bisexual, and transgender voters is called "Obama Pride: LGBT Americans for Obama."
The campaign describes it as "a way for LGBT people and allies to step up in this election and make sure President Obama gets a second term."
Gay voters could make a difference in close swing states with heavy urban populations.
Among the targets of Obama Pride: Pennsylvania, Colorado, Nevada and Michigan.