SANFORD, Fla. -

The judge presiding over George Zimmerman's second-degree murder trial has asked four more potential jurors to return for further questioning.
    
Judge Debra Nelson on Monday asked the candidates to come back Wednesday morning.

Prosecutors and defense attorneys are seeking a pool of 40 potential jurors who have been screened for any influence of pretrial publicity before moving to a second round of questioning. They must agree on six jurors and four alternates to hear the case.

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The number of potential jurors asked to return now stands at 32.
    
Zimmerman is pleading not guilty to murdering unarmed 17-year-old Trayvon Martin, saying he acted in self-defense.
    
The racial dimension of Martin's shooting was a prominent focus of questioning of potential jurors Monday.
    
A defense attorney questioned a potential juror extensively about her racial views on the case and whether she was bothered by protests led by civil rights leaders after Zimmerman's fatal shooting of 17-year-old Martin last year.
    
A 44-day delay in Zimmerman's arrest led to protests around the nation. Protesters questioned whether the Sanford Police Department was investigating the case seriously because Martin was a black teen from the Miami area. Zimmerman identifies himself as Hispanic.
    
The third juror questioned Monday morning was a middle-aged white woman who described the protests as unsettling and speculated that there could be further marches in Sanford if Zimmerman isn't convicted of second-degree murder. The jury candidate, who said she has a biracial grandson, also said she was unsure whether Zimmerman racially profiled Martin because it was dark and the Miami teen was wearing a hoodie, possibly making it difficult to see his race.
    
Zimmerman, a neighborhood watch volunteer, was walking through the community of townhouses where he lived when he spotted Martin walking back from a convenience store to a home belonging to his father's fiance. Zimmerman called a nonemergency police number, followed Martin and at some point there was a fight between them that left Martin dead.
    
Zimmerman is pleading not guilty to second-degree murder, claiming self-defense.
    
When asked if she thought it was wrong when Zimmerman ignored a police dispatcher's advice not to follow Martin, she answered "yes."
    
Prosecutors and defense attorneys are seeking a pool of 40 potential jurors who have been screened for any influence of pretrial publicity before moving to a second round of questioning. By Monday, they had interviewed 46 potential jurors over the past week.
    
Also interviewed Monday were an older white man who said he didn't have an opinion the case and a middle-aged black man who was dismissed after he said he would have trouble passing judgment on someone because of his religion. Attorneys also questioned a Hispanic mechanic in his 30s who said serving on a jury would be a hardship and a middle-aged white man who said he had donated $20 to Zimmerman's online legal defense fund.
    
It was the first encounter for attorneys with a potential juror who had donated to the fund. "It just seemed like he was underdog," the potential juror said of Zimmerman. "He couldn't go to work. He had to go into hiding. I just felt sorry for him."