Republican Devon Anderson saved her job by fending off Democratic challenger Kim Ogg in the Harris County District Attorney's race.

Anderson, a 48-year-old mother of two, was appointed as the Harris County District Attorney by Gov. Rick Perry to fill the vacancy created by the death of her husband, Mike Anderson, last year.

In the election held on Tuesday this week, Anderson received 53 per cent of total votes. Ogg received the remaining 47 per cent of the total votes cast on the Election Day.

Anderson dedicated her victory to her late husband, who died in 2013 following a brief battle with cancer. He served as the Harris County District Attorney for around eight months.

After being announced victorious, she said, "He made promises to the citizens of Harris County to restore the DA's office to its former glory. When the governor appointed me, I wanted to carry on those promises. I fulfilled some of them - we're working on others - but we're going to do it."

Ogg said that the tightly contested race for the office was big evidence that many Houston residents wanted change in the existing criminal justice system.

Last month, experts said the race the office of Harris County District Attorney was the only competitive race for Democrats, as many polls suggested that it was a dead heat because more than 40 per cent of voters remained undecided by that time.