WASHINGTON >> The Pentagon study that argues that gay troops could serve openly without hurting the military’s ability to fight is expected to re-ignite debate this month on Capitol Hill over repealing the 17-year-old “don’t ask, don’t tell” policy.

Officials familiar with the 10-month study’s results have said a clear majority of respondents don’t care if gays serve openly, with 70 percent predicting that lifting the ban would have positive, mixed or no results. The officials spoke on condition of anonymity because the findings hadn’t been released.

Defense Secretary Robert Gates and Chairman of the Joint Chiefs of Staff Adm. Mike Mullen, who have both said they support repealing the law, were scheduled to discuss the findings with Congress Tuesday morning and with reporters Tuesday afternoon.

Republicans, led by Sen. John McCain of Arizona, have mostly opposed repealing the law because they say efforts to do so are politically driven and dangerous at a time of two wars.

“This was a political promise made by an inexperienced president or candidate for presidency of the United States,” McCain told CNN’s “State of the Union” last weekend.

“The military is at its highest point in recruitment and retention and professionalism and capability, so to somehow allege that this policy has been damaging the military is simply false,” McCain said.

Democrats and gay rights groups counter that the study finally proves what they’ve known anecdotally for years: Most troops would accept an openly gay person in their units.

“It’s what we expected. The atmosphere in the active-duty has changed,” said a gay Air Force officer and co-founder of the advocacy group OutServe. The officer uses the pseudonym “JD Smith” to protect his identity.

The survey is based on responses by some 115,000 troops and 44,200 military spouses to more than a half million questionnaires distributed last summer. The study group, led by Pentagon General Counsel Jeh Johnson and Army Gen. Carter Ham, also visited various military bases and held town hall-style meetings with service members.

The findings of troop opinions would reflect the view of the broader population. According to a November survey by the Pew Research Center, 58 percent of Americans say they favor allowing gays to serve openly in the armed forces while 27 percent oppose.

The House has already voted to overturn the law as part of a broader defense policy bill. But Senate Republicans have blocked the measure because they say not enough time has been allowed for debate on unrelated provisions in the bill.

Senate Majority Leader Harry Reid, D-Nev., has promised a vote on the matter by the end of the year, after hearings can be held this week on the Pentagon study. Still, some gay rights groups have complained that Democratic leadership has done little to push for repeal before the new Congress takes over in January.

Reid spokesman Jim Manley said the majority leader is “very much committed to doing away with the ban this year” but that it was the GOP’s fault for blocking the bill.