Zimmerman, who identifies himself as Hispanic, fatally shot Martin a short time later following a confrontation that was partially captured on a 911 call.
Zimmerman, 29, is charged with second-degree murder. He is pleading not guilty, claiming self-defense.
The 40 potential jurors represent a cross-section of people from all walks of life and ethnic backgrounds who have varying levels of familiarity with the case’s basic facts.
Through an initial round of interviews that included questions focused on pretrial exposure to the case via the news media or other means, lawyers were able to find a group of potential jurors who said they could focus on testimony provided in the courtroom.
Nelson said attorneys for both the prosecution and the state would be allowed to ask much broader questions in the second round than they did in the first.
Nelson said last week that once pared down, the final jury would be sequestered throughout the trial to protect it from outside influence.
A white man in his 50s who described previously serving on a jury said he enjoyed the experience.
“Everybody hear that?” de la Rionda asked the jurors with a smile.
“It was one day. We weren’t sequestered,” the juror shot back.