Six days after a 41-14 loss to the Kansas City Chiefs unleashed criticism from Patriots doubters, the offense broke out of its season-long slump. Brady threw for 292 yards and Stevan Ridley had 117 of the team's 221 yards rushing against a team that had allowed an NFL-low 11 points per game.
The Patriots (3-2) surpassed that by scoring on their first two possessions on Ridley's 1-yard run and Brady's 17-yard pass to Tim Wright. They led 20-3 at halftime before the Bengals (3-1) cut it to 10 points on Andy Dalton's 37-yard pass to Mohamed Sanu.
But Cincinnati came no closer and became the last team to lose a game this season. The Arizona Cardinals also began the day at 3-0, but lost to the Denver Broncos.
The Bengals were coming off a bye and had trailed for just 48 seconds in their first three games. But they never led Sunday as Ridley scored just 4:57 into the game.
Stephen Gostkowski added five field goals, the most in his nine-year career.
Brady hadn't thrown for more than 249 yards this season but topped that as he completed 23 of 35 passes. His 27-yard completion to Rob Gronkowski put him over the 50,000-yard mark and he connected for Wright's touchdown on the next play.
The fans then chanted ''Bra-dee! Bra-dee!'' They shouted it again when the Patriots began a drive early in the second quarter.
Brady boosted his total to 50,232. John Elway is fifth with 51,475.
''It was a long week. We dug deep. (I'm) proud of everybody,'' Brady said.
Dalton was 15 of 24 for 204 yards and was sacked for the first time this season when Chris Jones tackled him 3 minutes into the fourth quarter. Dalton's second touchdown pass, a 17-yarder to A.J. Green made it 34-17.
But the Bengals lost three fumbles and failed to convert their seven third-down plays.
''If you turn the ball over and don't make any third downs, you have a chance to have this happen to you,'' Bengals coach Marvin Lewis said.
The Patriots were surrounded by doubters after the rout in Kansas City. Was Brady no longer one of the NFL's top quarterbacks? Did he have enough talented players around him - a rebuilt offensive line and mediocre receivers - to help him?
For one night, at least, he did.
''We don't sit around listening to what everybody else says,'' Patriots coach Bill Belichick said. ''We try to do the best we can.''
Brady was sacked just once and completed his first two passes, 20 yards to Brandon LaFell and 30 yards to Wright, who had his best game since being acquired from Tampa Bay just before the season for six-time Pro Bowl guard Logan Mankins.
Not a bad start for a quarterback who had led the Patriots to only 46 points in the previous 14 quarters.
Brady got plenty of help from his defense, which allowed just 121 yards in the first half, and his special teams as Kyle Arrington scored on a 9-yard return after recovering Brandon Tate's fumble on a kickoff. That made it 34-10 just 6 seconds after Brady's 16-yard touchdown pass to Gronkowski.