Nathan was born in Richland County and, for almost two decades, has worked, lived, and raise his family in the community named after his ancestors. Nathan and his wife Karen are involved in Riverland Hills Baptist Church. He has a step-daughter, Sarah Katherine, son Jonathan Carroll, Jr., and daughter Emma Logan. Before his election to the South Carolina House of Representatives in 2004, Nathan had been involved with and supported community groups such as the Lake Murray/Irmo Rotary, home owners associations, the District Five Government Relations Committee, the Community Leadership Council and the Northwest YMCA Advisory Council. He was a member of Leadership Columbia and the University of South Carolina Young Alumni Council and the University's Richland/Lexington Alumni Council. Nathan has worked for the same company since graduating from the University of South Carolina in December 1992 and is Vice President and Branch Manager for Wells Fargo Home Mortgage in Columbia, South Carolina.
On June 8, 2004, Nathan defeated the 16-year incumbent, Rick Quinn, who served as the House Majority Leader. After the upset in the Republican primary, the Ballentine easily defeated the Green Party candidate in November 2004 general election. Ballentine was elected Vice Chairman of the Medical, Military, Public and Municipal Affairs committee during his freshman year. He worked to get the first bill he filed to become law. In three months, became law and the Palmetto State soon benefitted from an increased focus on geriatric medicine. In just his 2nd year in office, Nathan again focused on healthcare; this time focusing on autistic children. Even though ; Nathan’s hard work enabled similar legislation to pass the following year. Another re-election provided an opportunity to push fiscal issues that led to the passage of and a House Rule change banning hidden earmarks. During 2009 and 2010, Nathan was the chief cosponsor, with then-Representative Nikki Haley, pushing for more accountability with On-The-Record Voting. That bill ultimately died in the Senate; but not before the House made a rule change and passed the bill with no dissenting votes. In 2011 at the request of Governor Haley, Nathan became lead sponsor for the and is hopeful for passage of one of the Governor's top issues to improve accountability in the SC General Assembly. In the 2010 session, Nathan’s became law. The bill requires every elected official to file their campaign disclosure report on-line. During his career in the South Carolina General Assembly, Ballentine has served on the Education and Public Works Committee, the House Ethics Committee, the Joint Transportation Review Screening Committee, and has been named a Friend of the Taxpayer and Taxpayer Hero every year he has served in Columbia. He receives high grades from as well as the and the . Nathan is the Chairman of the Regulations Subcommittee in the House Agriculture, Natural Resources and Environmental Affairs Committee. Nathan does not keep his State House salary, donating it to community groups and organizations. In 2006, he designated funds for scholarships for deserving seniors. In his six years in office he has returned over $40,000 to his community.
