Thome hit his 535th homer to gain sole possession of 15th place, and the White Sox beat the Baltimore Orioles 4-3 Monday night after losing the completion of a game suspended by rain.
The "split" enabled the White Sox to move a game ahead of Minnesota as the Twins fell to Seattle in 11 innings later Monday.
"Anytime you got a team like Minnesota that's right there [and] we're getting close to September, that kind of enhances it," Thome said.
Thome's 28th homer of the season gave the White Sox a 4-3 lead in the sixth. The drive, off Baltimore rookie Chris Waters, moved Chicago's designated hitter past Jimmie Foxx and put him within one of Mickey Mantle on baseball's home run chart.
"Very special," Thome said. "We've talked about it. Anytime you can tie or move ahead of the greats that played the game, it's very humbling. It's something you look back and feel very honored. You cherish that, for sure."
Earlier, Lou Montanez singled in the tiebreaking run in the 14th inning to give the Orioles a 4-3 victory in a game halted in Chicago after 11 innings on April 28.
With the score 3-all in the finale of a four-game series in Chicago, play was stopped with the infield unplayable. It was the Orioles' final scheduled visit, so baseball officials ruled that the game would be completed in Baltimore -- with the White Sox playing the strange role of the home team at Camden Yards.
In the regularly scheduled game, White Sox rookie Clayton Richard (2-2) gave up three runs and six hits in six innings to outpitch Waters (2-1), who allowed four runs and five hits in seven innings but absorbed his first loss in the big leagues.
"It's nice to win this one. It hard, after the first game. It gets you down," White Sox manager Ozzie Guillen said. "We come back and played great baseball."
Thome struck out twice against Waters before connecting in the sixth, his second homer in two games and eighth in August.
"Thome has been my favorite player since I was old enough to know about him with the Indians," Waters said. "It was good to get him out the two times, but I left a mistake right there for him the last one."
In the suspended game, Baltimore's Nick Markakis led off the 14th with a single off Horacio Ramirez (1-3). After a single by Millar, a sacrifice and an intentional walk loaded the bases, Montanez greeted D.J. Carrasco with a soft single to center.
Alberto Castillo (1-0) got the final out in the 13th to earn his first major league victory, and Cherry picked up his first big league save.
Neither Castillo nor Cherry was on Baltimore's roster when the game began in April.
Both managers were allowed to insert newcomers into the lineup, but those removed from play were not allowed to return. Baltimore was forced to play without Aubrey Huff, who was ejected in the 10th inning in April for arguing a play at first base.
The Orioles resumed the game with no bench players because Alex Cintron replaced Huff at DH, Juan Castro took over for departed shortstop Brandon Fahey, and Montanez subbed for center fielder Adam Jones, who is on the disabled list.
"The first game was kind of a weird deal," Thome said. "Our lineup has changed since the lineup was out there, so we were looking at the lineup card to see where we were all at. Unfortunately, we didn't pull it out."
Chicago activated 3B Joe Crede from the DL before the suspended game and he took his original place in the lineup. ... Hernandez extended his career-best hitting streak to 15 games. ... After the game, the Orioles optioned RHP Kam Mickolio to Triple-A Norfolk and recalled LHP Brian Burres, who will start Tuesday against Chicago.
Information from The Associated Press contributed to this report.