Proponents of the politically correct social engineering scheme of introducing open homosexuality into the military used a highly unrandomized sample, which is not credible, in hopes to affect public opinion and garner support for their cause.
This study is pure propaganda meant to advance the homosexual agenda just as the president said he would do. (see article)(see 2:50min video)
Politicians know that most people are poorly trained in logical thought, and in the politician’s own thinking, it is for the greater good to manipulate poor logical thought to lead their constituents toward the "correct" stance. In this case acceptance of the repeal of DADT, which is what the Soetoro administration intends to do. The administration only wishes to sway public opinion by making it seem that Americans are approving of the repeal of DADT.
The DoD in this case, worded this poll and distributed it in a manner they thought would reflect their views, they polled a demographic that responded the way they thought it would and call it a survey (a real scientific survey would have to pass peer review).
This was an asked for and delivered finding. The DoD and the Soetoro administration were looking for approval for homosexuality so they could announce the finding and subsequently end DADT and they found it. This study is not worth the paper it is written on.