What was a very bad day for Ahmed Ghailani, now a convicted felon likely to spend many years in a supermax prison, was also, because of the super-charged politics surrounding Guantanamo Bay, a pretty bad day for the Obama administration.

To be sure, the 36-year-old Tanzanian was convicted Wednesday of one count of conspiracy in federal court in New York. In addition, Ghailani could well serve life in prison for his role in the 1998 U.S. embassy bombings in East Africa by al-Qaeda. And it's at least debatable whether the outcome would have been different in a military commission in Cuba.

But the political reality is that the prospect of a tough sentence for conspiracy to destroy U.S. property by fire or explosives was largely swallowed up by a stunning verdict in which Ghailani was acquitted of 284 counts, including all 224 murder counts.

Across the administration, from the White House to the Justice Department, and among some human rights advocates, there was private dismay that the first trial of a Guantanamo Bay detainee brought into the United States did not result in a clear and unequivocal conviction on all counts.

Neither President Obama nor Attorney General Eric H. Holder Jr. commented publicly on the verdict, which other officials said they interpreted as a sign of quiet defeat. The political climate for civilian trials will grow only worse in January once Republicans - who are widely opposed to using federal courts to prosecute Guantanamo detainees - take over the House, officials said.

"There's no political will for it," said one official directly involved in Guantanamo issues, speaking of federal trials.

Even before the jury of six men and six women issued its verdict, Obama was facing some determined and bipartisan opposition to further civilian trials of Guantanamo Bay detainees. After the verdict, the president's political adversaries are likely to be even more unyielding.

On the Senate floor Thursday, Republican Minority Leader Mitch McConnell (Ky.) said the president should offer assurances that "terrorists will be tried from now on in the military commission system that was established for this very purpose at the secure facility at Guantanamo Bay, or detained indefinitely, if they cannot be tried without jeopardizing national security."

Senior administration officials expressed frustration with the Republican response to the Ghailani case, saying the verdict changed nothing about the legal viability of civilian courts to handle terrorist cases. "Ghailani is an unfortunate addition to a long-running saga of politicization and outright distortion of this issue," one official said.

Had the jury found Ghailani not guilty on all counts, as at least seems possible now, it could have resulted in the extraordinary spectacle of the Obama administration ignoring the judgment of a jury of ordinary Americans and returning Ghailani to military custody and possibly his old cell at Guantanamo Bay's Camp 7 detention center. That is a scenario also likely to temper judgments about proceeding with other civilian trials.

At the Justice Department, spokesman Matthew Miller said "one of the strengths of the criminal justice system is its ability to handle difficult cases.

"This was a difficult case in that there were questions about Ghailani's treatment during the previous administration" - such as the use of enhanced interrogation techniques - "that led to a key witness being excluded," he said.