BOSTON — The judge in the federal death penalty trial of Boston Marathon bombing suspect Dzhokhar Tsarnaev said Monday that he’s not discouraged by the slow pace of jury selection.

“We’re making good progress,” Judge George O’Toole Jr. said on the day testimony had been expected to begin.

Instead of listening to opening statements and the first witnesses, O’Toole was questioning prospective jurors for a seventh day. The judge had originally said he hoped to question 40 potential jurors each day. But so far, the average number of jurors questioned has been about 14 per day.

O’Toole said he has taken steps to hasten the process, including by screening written juror questionnaires ahead of time to excuse people with hardship.

His comments to prosecutors and Tsarnaev’s lawyers came just as he told them he would not call in any jurors Tuesday because of an impending blizzard. The snowstorm is expected to dump 2 to 3 feet of snow on the region, beginning Monday night.

O’Toole said it is “iffy” whether any jurors will be called to court Wednesday, depending on the length and severity of the storm.

Three people were killed and more than 260 were injured when twin bombs exploded at the marathon finish line on April 15, 2013.

Tsarnaev, 21, has pleaded not guilty to 30 federal crimes, including 17 charges that carry the possibility of the death penalty.

Prospective jurors have been questioned at length about whether they have already formed an opinion on Tsarnaev’s guilt and their feelings about the death penalty.

Massachusetts abolished its state death penalty three decades ago, and numerous attempts to reinstate it have failed in the state Legislature. Tsarnaev is being prosecuted under the federal death penalty statute.

Many of those questioned so far have said they could not be impartial because they already believe Tsarnaev is guilty. Some prospective jurors have said they would find it difficult, if not impossible, to vote for the death penalty. Others have said they could impose it if the facts of the case and the law call for it.

Tsarnaev’s lawyers have asked repeatedly to move the trial outside Massachusetts because they believe he cannot get a fair trial here because of the publicity and the personal connections many people have to the marathon and the bombings. O’Toole has not ruled on the latest defense request, filed last week.

Prospective jurors questioned Monday included a nurse who said she found it difficult to watch television coverage of the bombings, particularly when injured people were shown. “I would be very emotional. … My daughters would have to shut off the TV,” she said.

The judge then stopped questioning the woman. He has not revealed how many of the people questioned so far have been excused.

Another woman who works as a risk manager for a construction company wrote on her juror questionnaire that “it’s an honor to be asked to serve.” She told the judge she believes the right to a fair and impartial trial is “the single most important right” we have.