Survivors have generally kept their views on the death penalty to themselves, but some began to speak out after the verdict.

Jarrod Clowery, who suffered burns and multiple shrapnel wounds, said on NECN television, a local cable channel, that he thought Mr. Tsarnaev was trying to get killed during the shootout with police in Watertown and expressed doubts about whether the death penalty would be the right punishment. “Why give him what he wants?” Mr. Clowery asked.

After the verdict, The Boston Globe ran an editorial urging that Mr. Tsarnaev be spared the death penalty.

The jury is already “death qualified”: That is, only those who said they were open to applying the death penalty were allowed to serve, while those who flatly opposed it were excluded. Many of those who were chosen said they were open to the argument either way. The question now is the degree to which a jury that so thoroughly embraced the government’s case might be inclined to accept the argument that Mr. Tsarnaev’s crimes were so heinous that he deserved to die.

A poll of Boston voters taken in the midst of the trial, when witnesses were giving the most heart-wrenching testimony, found that 62 percent of Bostonians said they would sentence Mr. Tsarnaev to life; only 27 percent said he should be put to death. In the Boston metropolitan region, 49 percent favored life, compared with 38 percent who opted for death. But the jury is drawn from Eastern Massachusetts, beyond the Boston region, so it is not clear how much these sentiments reflect the views of the 12 who will make the decision.

Martin G. Weinberg, a prominent defense lawyer in Boston, said that the guilty verdicts had been pre-ordained by the defense team’s admission at the outset that Mr. Tsarnaev was involved, and that he did not see them as an unexpected setback.

The defense strategy of admitting to the crime and casting Mr. Tsarnaev as a subordinate to his older brother, he said, was not intended to get him acquitted in the first phase but to lay the groundwork for the sentencing phase. “The defense retained its credibility to say to the jury, ‘We are asking you to save his life because he wasn’t the engineer, the architect of the bombings,’” Mr. Weinberg said.