They will be back at the courthouse Friday.
Balfour, who turned 31 on Thursday, is charged with three counts of first-degree murder in the October 2008 slayings of Darnell Donnerson, Jason Hudson, and Julian King, 7.
Jurors arrived at the courthouse around 10:15 a.m. Thursday. Many of them were wearing the same clothes they had on Wednesday after being sequestered over night by Judge Charles Burns. They spent the day deliberating, breaking for lunch and dinner.
The racially diverse jury of six men and six women is weighing the state's circumstantial case. Prosecutors say Balfour killed Jennifer Hudson's mother, brother and nephew over jealousy. They say bal four carried through on threats he had made to his estranged wife, Julia Hudson, who refused his attempts to get back together.
The defense suggested Jason Hudson's drug dealing business led to the murders.
The jury began deliberations late Wednesday afternoon after four hours of closing arguments. During those arguments, prosecutors suggested for the first time that Balfour had help in the murders. Prosecutors told jurors someone else drove Balfour's car away from the murder scene while Balfour left the Hudson family's Englewood home in Jason's white suburban. Julian King's body was found inside that SUV three days after the other bodies were found.
Balfour's attorney blasted the mysterious accomplice theory and told jurors from the day of the murders police were building their case against Balfour rather than investigating the crime.
During the trial, prosecutors presented 81 witnesses and close to 500 pieces of evidence.
Jennifer Hudson was not spotted in court on Thursday, but she has attended every day of the trial. Officials say that while she may not be in the courthouse during deliberations, she is near. On Wednesday, the singer stayed until 9:30 p.m., when the jury was taken to an undisclosed hotel.