Curtis, 70, a retired schoolteacher, survived a low voter turnout in getting 289 votes. That was 70 more than those received by her opponent, businessman Charlie Hannah, 43.
The runoff was needed because Curtis captured 2,122 votes, or 47 percent, in a four-way race in the Nov. 2 general election. Hannah, who owns and operates Jazzy Shots Photography, came in second that day with 1,072 votes, or 23.7 percent.
In the general election, 4,516 votes were recorded in the District 2 race, which was a turnout of 45.7 percent. In the runoff, only 514 ballots were cast, a turnout of just 4.5 percent.
"Any time you have to go back that second time, the people don't go back," Curtis said. "Another thing is, the younger people are not voting. They just don't see it yet."
Curtis said she is delighted to return for a fourth term: "I'm happy I won and it's all over."
She said she hopes to encourage parents to be involved in their children's education, with the result that test scores will improve.
"I will try to get them to really work with their teachers and work with their children so they can do better on the test," Curtis said. "That's a grave concern."
In statewide runoffs, Georgia Supreme Court Justice David Nahmias kept his post on the state's top court, while lawyer Chris McFadden pulled off a come-from-behind win for an open seat on the state Appeals Court.
Unofficial returns showed Nahmias winning 68 percent of the vote, compared with 32 percent for Lawrenceville lawyer Tammy Lynn Adkins with 92 percent of precincts reporting in the nonpartisan race.
Republican Gov. Sonny Perdue appointed Nahmias to the bench in 2009.
During the campaign, Nahmias, 46, touted his Republican credentials as a former clerk for U.S. Supreme Court Justice Antonin Scalia. He also served as a leading terrorism prosecutor in the U.S. Justice Department until President George W. Bush appointed him U.S. attorney in Atlanta in 2004.
McFadden, 53, garnered 63 percent of the vote, compared with 37 percent for Antoinette Davis, a 59-year-old lawyer from Marietta, with 92 percent of precincts reporting.
Associated Press reports were used in this article.