Votto was activated off the disabled list before the game, but didn't play. Cincinnati went 32-16 without him, taking control of the NL Central.
Bruce's 31st homer in the sixth inning ended a four-game winning streak by Kyle Kendrick (8-10). Bruce has homered in four of his last five games.
Mat Latos (12-4) gave up one run - on a bases-loaded walk - and four hits in seven innings.
Jimmy Rollins doubled off Latos in the fifth inning, making him the fourth Phillies player to reach 2,000 career hits. He joined Mike Schmidt (2,234), Richie Ashburn (2,217) and Ed Delahanty (2,207).
Left-hander Aroldis Chapman gave up a walk and fanned two while getting his 35th save in 39 chances. Chapman has converted 27 straight save opportunities since June 24, a franchise record.
The win evened the season series at three games apiece. Philadelphia has been one of Cincinnati's toughest opponents, winning nine of their last 12 games. The Phillies have won their season series each of the past seven years.
Cincinnati's surge into playoff position has attracted bigger crowds to Great American Ball Park. The Reds topped 2 million in season attendance on Tuesday night, the fastest they've reached the mark since the ballpark opened in 2003.
Latos, the Reds' biggest offseason acquisition, was in the middle of all the early action. He got picked off third base by catcher Erik Kratz in the third inning, ending a rally. He then helped the Phillies pull ahead 1-0 in the fourth because of his control problems.
Philadelphia loaded the bases when Chase Utley doubled, Latos hit Ryan Howard on the arm, and John Mayberry Jr. walked with one out. Latos then walked Domonic Brown - in an 0-for-18 slump - on four pitches to force in a run.
Nate Schierholtz followed with a sinking liner that center fielder Drew Stubbs appeared to catch on the short hop. Second base umpire D.J. Reyburn ruled it a catch, then called a forceout at second when Stubbs threw to the infield with confused Phillies trying to figure out what to do.
NOTES: Rollins' double also gave him a seven-game hitting streak. ... The Reds recalled RHP Todd Redmond and RHP Pedro Villarreal from Louisville, promoted LHP Tony Cingrani from Double-A Pensacola, and outrighted INF Chris Valaika and RHP Jordan Smith to Louisville. ... The Phillies called up INF/OF Pete Orr from Triple-A Lehigh Valley. ... Bengals QB Andy Dalton threw a ceremonial pitch to WR A.J. Green. ... Latos failed to get a hit, snapping his career-high six-game hitting streak.