The Texas secretary of state's office on Friday said that there have been issues reported with Hart eSlate voting machines, which are used in approximately 30 percent of counties statewide. The machines feature a wheel for selecting candidates and buttons to move from screen to screen.

But the secretary of state's office said the issues were not caused by the voting machines, but by voters themselves.

"The Hart eSlate machines are not malfunctioning, the problems being reported are a result of user error — usually voters hitting a button or using the selection wheel before the screen is finished rendering," said Sam Taylor, spokesman for the office of Secretary of State Rolando Pablos.