"When you play your big brother, you want to do whatever it takes to win," McNabb said of facing Dawkins, one of the greatest defensive players in team history.
Rookie wide receiver Jeremy Maclin set up Akers' kick with an outstanding, 27-yard catch along the sideline to the Broncos 13. The catch initially was ruled incomplete, but it was overturned after replays showed Maclin kept both feet inbound while making a diving reception.
Three plays later, Akers nailed a gimme.
"I just want to be reliable in the key moment," Maclin said.
The Eagles (11-4) can clinch their sixth NFC East title this decade with a victory at Dallas (10-5) next Sunday. The winner of that game takes the division crown. Also, a victory over the Cowboys coupled with one loss by Minnesota would give Philadelphia a first-round bye in the playoffs.
The Broncos (8-7) are trying to avoid a major collapse after starting 6-0. They no longer control their playoff destiny and are tied with four other teams for the final two wild-card spots in the AFC.
McNabb threw for 322 yards and three TDs, tight end Brent Celek had 121 yards receiving and one TD and Philadelphia won its sixth straight game.
The Eagles have set a franchise record for most points in a season, surpassing the 416 they scored last year. They have 429 points, an average of 28.6 per game.
A seven-time Pro Bowl safety in 13 seasons in Philadelphia, Dawkins returned in a Broncos uniform after leaving in free agency.
Dawkins, who didn't come out for pregame warmups, received a rousing ovation when he was introduced. He went through his familiar routine, gyrating and contorting his way onto the field. Dawkins turned a backward, rolling somersault into a reverse handstand before sprinting down the line and nearly taking out a camera man.
He hugged teammates after the game and blew kisses to the fans as he ran off the field.
"It's just real, real nerve wracking," Dawkins said. "I've been in a lot of big games before. I was just trying to control my emotions. It was real tough for this game, mainly because we needed this game so bad."
Orton began Denver's comeback bid with a 7-yard TD pass to Jabar Gaffney, completing a drive that started at the Philadelphia 25 after a short punt, 11-yard return and a penalty.
Macho Harris fumbled the ensuing kickoff following a hard hit by Darrell Reid and Robert Ayers recovered at the Eagles 16. Orton then hit Knowshon Moreno over the middle for a 16-yard TD that cut it to 27-24.
The teams traded three-and-outs on the next five possessions until the Broncos converted on third-and-2. Orton found Gaffney for an 18-yard gain to the Eagles 30. Matt Prater then kicked a 46-yard field goal to tie it at 27 with 6:05 left.
Facing a third-and-25 from their 15, the Eagles finally got a first down when McNabb scrambled 27 yards up the middle. But the offense stalled again. Sav Rocca pinned the Broncos back to their 9 with a 40-yard punt. The change in field position helped set up Philadelphia's winning drive.
Brian Westbrook returned for the Eagles after missing seven of the past eight games with concussions. He hadn't played since sustaining his second concussion in a three-week span on Nov. 15 at San Diego. The former All-Pro running back had 32 yards rushing on nine carries.
McNabb connected with DeSean Jackson on a 2-yard TD pass to put the Eagles ahead 7-0 in the first quarter. Dawkins missed a tackle on LeSean McCoy's 39-yard catch-and-run on the first play of the drive.
Orton threw an 11-yard TD pass to Gaffney to trim Philadelphia's lead to 10-7 in the second. Gaffney bounced off two tacklers after catching the pass inside the 5 and scooted into the end zone.
McNabb tossed a 47-yard TD pass to a wide-open Celek, giving the Eagles a 17-7 lead in the second quarter. Dawkins may have missed coverage on the play because he pointed at his head and chest after the catch.
Helped by two Broncos penalties, including a 41-yard pass interference call on Champ Bailey, the Eagles went ahead 27-10 midway through the third quarter. McNabb connected with Jason Avant on a 15-yard TD pass. Safety Renaldo Hill tipped the ball and Avant made a juggling catch as he fell backward into the end zone.
A touchdown that would've given the Eagles a 7-0 lead was overturned when a replay showed that Orton's incompletion was a forward pass. Thinking Orton made a backward pass, Dimitri Patterson picked up the ball and ran it back 23 yards for a score.
Dawkins committed a penalty on Philadelphia's first possession that almost proved costly. He was called for illegal contact on third-and-7, negating a sack that would've forced a punt. The Eagles then drove to the Broncos 19, but Elvis Dumervil sacked McNabb and Reid recovered it. Dumervil tied Simon Fletcher's franchise record with his 16th sack.
Eagles C Jamaal Jackson left with a knee injury. He's scheduled for an MRI on Monday. ... Michael Vick was the third QB for the Eagles. He missed practice all week with a quad contusion. ... Broncos KR Kenny McKinley left with a knee injury. Denver was without WR/KR Eddie Royal. ... WR Brandon Lloyd made his Broncos debut after being inactive the entire season. ... Eagles CB Asante Samuel made his ninth interception. Bill Bradley had 11 in 1971.