Juror B29 told Robin Roberts that she favored convicting Zimmerman of second-degree murder when deliberations began by the six-member, all-women jury.
"I was the juror that was going to give them a hung jury," she said. "I fought to the end."
But by the second day of deliberating, she realized there wasn't enough proof to convict the 29-year-old neighborhood watch volunteer of a crime.
"George Zimmerman got away with murder, but you can't get away from God," she said. "And at the end of the day, he's going to have a lot of questions and answers he has to deal with."
Zimmerman was acquitted earlier this month of second-degree murder and manslaughter charges in the 2012 slaying of the unarmed 17-year-old. The Miami teenager was shot and killed during a confrontation with Zimmerman in Sanford. The case spawned heated national debates about racial profiling and the so-called Stand Your Ground self-defense laws in Florida and other states.
Zimmerman was seen publicly for the first time last week when he assisted a family after their SUV flipped over on a Florida highway.
Juror B29 is the second panelist to go public with what went on during deliberations earlier this month.
Four jurors, not including the one interviewed by ABC, issued a statement last week saying the opinions expressed by Juror B37 to CNN's Anderson Cooper did not represent their views.
That juror said the actions of Zimmerman and Martin both led to the teenager's fatal shooting, but that Zimmerman didn't actually break the law.
Juror B29 also told ABC that she didn't believe race was an issue at the trial. Though the judge so far has refused to release the names or biographical information about the jurors, B29 said she was 36 years old and Puerto Rican.
Martin was black and Zimmerman identifies himself as Hispanic. Martin's parents believe Zimmerman racially profiled their son when he started following him after spotting him walking through the neighborhood where Zimmerman lived and Martin was visiting. B29 said she couldn't speak for her fellow jurors on the race issue. The other women on the jury were white.
Juror B29 is a nursing assistant and mother of eight children who recently moved to Florida from Chicago.
She said she feels like she owes Martin's parents an apology.
"I felt like I let a lot of people down, and I'm thinking to myself, 'Did I go the right way? Did I go the wrong way?'" she said. "As much as we were trying to find this man guilty ... They give you a booklet that basically tells you the truth, and the truth is that there was nothing that we could do about it."