The Boy Scouts of America has said it may soon give sponsors of units the authority to decide whether to accept gays as scouts and leaders.
It would be a potentially dramatic retreat from a nationwide no-gays policy that has provoked relentless protests.
Under the change now being discussed, the different religious and civic groups that sponsor scout units would be able to decide for themselves how to address the issue.
They could either maintain an exclusion of gays, as is now required of all units, or open up their membership.
Gay-rights activists were elated at the prospect of change, sensing another milestone to go along with recent advances for same-sex marriage and the end of the ban on gays serving openly in the US military.
However, Southern Baptist leaders, who consider homosexuality a sin, were furious about the possible change.
They said its approval might encourage Southern Baptist churches to support other boys' organisations instead of the BSA.
The announcement of the possible change comes after years of protests over the no-gays policy, including petition campaigns that have prompted some corporations to suspend donations to the Boy Scouts.
BSA spokesman Deron Smith said that under the proposed change "the Boy Scouts would not, under any circumstances, dictate a position to units, members, or parents".
Mr Smith said the change could be announced as early as next week, after BSA's national board concludes a regularly scheduled meeting on 6 February.
The meeting will be closed to the public.
The BSA, which celebrated its 100th anniversary in 2010, has long excluded both gays and atheists.
Mr Smith said a change in the policy toward atheists was not being considered, and that the BSA continued to view "Duty to God" as one of its basic principles.
Protests over the no-gays policy gained momentum in 2000, when the US Supreme Court upheld the BSA's right to exclude gays.
Scout units lost sponsorships by public schools and other entities that adhered to non-discrimination policies, and several local scout councils made public their displeasure with the policy.
More recently, shipping giant UPS Inc and drug-manufacturer Merck announced that they were halting donations from their charitable foundations to the Boy Scouts as long as the no-gays policy was in force.