The Cubs hit back-to-back homers twice in the fourth inning -- the second straight day they've hit consecutive homers against their city rivals -- and finished with 15 hits. They've now won 13 straight at Wrigley Field, where they are 31-8 this season.
The White Sox led 4-1 after two-run homers from Jermaine Dye and DeWayne Wise, before the Cubs jumped all over Jose Contreras, combining eight hits, including the four homers, into their biggest inning of the season.
Edmonds, who'd missed the two previous games with a sore foot, and Fontenot homered on consecutive pitches from Contreras to get the fourth inning rolling and cut the lead to one.
After Ryan Theriot walked and Cubs' starter Jason Marquis singled, the Cubs followed with three RBI singles from Kosuke Fukudome, Eric Patterson and Derrek Lee for a 6-4 lead. It was the third hit of the game for Patterson, who was just recalled from the minors Saturday.
Ramirez -- the hero of Friday's 4-3 victory with the game-tying and game-winning homers -- then dealt the White Sox a crushing blow, a three-run shot to left just over the wall to finish Contreras (6-6). Contreras' line wasn't pretty: 3 1-3 innings, 10 hits and nine earned runs.
Boone Logan relieved and Edmonds greeted him with another line drive into the left field bleachers to make it 10-4 and send the Cubs' crowd into a full-fledged tizzy on a 70-degree day at Wrigley Field.
The outburst made it easy for Marquis (6-3) to win his fourth straight start and fifth straight decision. He gave up eight hits and five runs in seven innings and also collected two hits.
Dye homered for a third straight game, a two-run shot in the first. His 16th homer of the season was also his sixth in the last six games.
Wise, brought up from the minors on Tuesday, hit his first homer since Oct. 3, 2004 -- with the Braves at Wrigley Field -- and just the 10th of his career to give the White Sox a 4-1 lead.
Ramirez also had an RBI single in the first.
The White Sox got a run in the eighth when Cubs reliever Carlos Marmol walked the bases loaded and threw a wild pitch before retiring the side with Jim Thome in the on-deck circle. Dye singled in a run off Bob Howry in the ninth to slice it to 11-7 before Kerry Wood came on to strike out Nick Swisher with two runners on to get his 19th save in 23 tries.
Game time on Sunday is 7:05 p.m. at Wrigley Field.