The effort will shift tens of millions of dollars in the next few years to what advocates described as the final frontier for gay rights: states like Mississippi, Georgia, Arkansas and Texas, where Republicans dominate elected office and traditional cultural views on homosexuality still prevail.

The new strategy reflects the growing worry within the movement that recent legal and political successes have formed two quickly diverging worlds for lesbian, gay, bisexual or transgender Americans: one centered on the coasts and major cities, and another stretching across the South and up through the Rocky Mountains, in states where gays enjoy virtually no legal protections against discrimination.

“We can’t allow two distinct gay Americas to exist,” said Tim Gill, a Colorado philanthropist whose foundation is putting about $25 million into a handful of mostly conservative-leaning states over the next five years. “Everybody should have the same rights and protections regardless of where they were born and where they live.”

The push is likely to encounter resistance.