Gerald Henderson finished with 17 points and Ramon Sessions had 16 for Charlotte.
The Hawks are 12-3 since losing three of their first five games this season. Atlanta has won two straight and five of six, and it erased a half-game deficit behind idle Miami for a share of the Southeast Division lead.
Lou Williams had eight of his nine assists in the first half for Atlanta. Williams, who finished with 13 points, matched his career high in assists, and Ivan Johnson added a season-high 16 points.
Hawks center Al Horford finished with 11 points and three rebounds, ending his streak of seven consecutive double-doubles.
Atlanta got off to a strong start offensively, hitting nearly 63 percent of its first 35 shots before Horford and Williams missed jumpers to end the first half.
Charlotte shot 35.9 percent and trailed by 17 at the break.
Since winning in double overtime at Washington on Nov. 24 and improving to 7-5, the Bobcats have looked similar to the Charlotte team that finished last season 7-59 for the worst winning percentage in NBA history.
The Bobcats were coming off a dispiriting home loss Wednesday to the Los Angeles Clippers in which they blew a seven-point lead in the fourth quarter.
When Charlotte last visited Philips Arena on Nov. 28, the game was decided on Horford’s late free throws and a missed 3-pointer by Hornets forward Byron Mullens.
The Hornets were led that night by Ben Gordon, who scored 20 of his 26 points in the fourth quarter. On Thursday, Gordon had just seven points on 2-for-9 shooting.
Hawks guard Kyle Korver, playing for the second straight night after returning from a five-game absence caused by back spasms, finished with 13 points in 22 minutes.
Williams hit consecutive 3-pointers to give Atlanta its first double-digit lead at 26-14 late in the first quarter. Harris hit a 3 midway through the second that made it 45-28.
Smith’s third-quarter dunk gave the Hawks a 66-43 lead early in the third.
NOTES: Hawks starting F DeShawn Stevenson scored nine points after missing Wednesday’s win at Orlando with a knee injury. ... Atlanta improved to 4-0 on the second night of back-to-backs. ... The Hawks have won seven straight against Charlotte, including three meetings this season.