Matt Prater's 51-yard field goal 6½ minutes into OT won it after his 59-yarder with 3 seconds left in regulation tied the score.
It was Denver's sixth straight win and seventh in eight games since Tebow was promoted to starter. The Broncos have trailed in the second half in six of those victories.
This latest comeback put Denver in sole possession of first place in the AFC West after Oakland's 46-16 drubbing at Green Bay.
After failing to score on their first dozen possessions, the Broncos (8-5) erased a 10-0 deficit in the final 2:08 of regulation.
Tebow hit Demaryius Thomas with a 10-yard TD pass, then got the ball back with 53 seconds left after Marion Barber saved the Broncos precious time by going out of bounds when the Bears were trying to run out the clock.
Denver was out of timeouts after Thomas' touchdown and had to try an onside kick, which the Broncos couldn't recover. But on second down after the two-minute warning, Barber cut outside and was pushed out, stopping the clock.
The Bears would have to punt, and Tebow got the ball back at his 20 and went to work, not needing to go far with Prater's strong leg in the thin air.
He drove the Broncos 39 yards for Prater's kick, which he rocketed through the uprights.
"We missed the onside kick. Then, all of a sudden, Barber goes out of bounds and gives us a chance," Bailey marveled. "We knew right then we still had a fighting chance. If you give our offense a chance in the end, good things might happen."
The Bears (7-6) won the toss in overtime and quickly got into field goal range before Barber, who rushed for 108 yards but will be remembered for his two late mistakes, coughed up the football at the Broncos 34, and Elvis Dumervil recovered.
Barber had already broken through the first line of defense for the first down when linebacker Wesley Woodyard reached out and grabbed his right arm, popping the ball loose.
"It's crazy," Bailey said. "He has a free lane to run. All of a sudden, somebody snatches the ball out. Wow! We made a play when we had to. We hadn't had a turnover all day."
GIANTS 37, COWBOYS 34
At Arlington, Texas, Eli Manning ended New York's four-game losing streak in style, leading the Giants to two touchdowns in the final 3:14 in a showdown for first place in the NFC East.
Dallas appeared to tie the game with a 47-yard field goal as time expired, but New York called a timeout. Given another chance to force overtime, rookie Dan Bailey's kick was blocked by Jason Pierre-Paul — who also had a sack for a safety and forced a fumble.
The Giants (7-6) and Cowboys are tied atop the division, but this victory gives New York the inside track. The teams will meet again in the season finale, on New Year's Day, at the Giants' home field.
Dallas lost its second straight.
TEXANS 20, BENGALS 19
At Cincinnati, rookie T.J. Yates led the biggest drive in Houston Texans history, throwing a 6-yard touchdown pass with 2 seconds left for a 20-19 victory that brought the first playoff berth in franchise history.
With their seventh straight win, the Texans (10-3) moved to the threshold of their first playoff berth. They clinched the AFC South title a few minutes later when Tennessee lost to New Orleans.
Cincinnati (7-6) couldn't prevent the Texans from going 80 yards in the closing minutes behind their third quarterback in the last four games. Yates' 6-yard throw to Kevin Walter — uncovered at the goal line — set off a celebration on the Houston sideline.
SAINTS 22, TITANS 17
The NFC South-leading Saints (10-3) had little trouble picking up yards, but struggled to score until Brees and Colston connected on passes of 35 and 28 yards.
The Titans (7-6) twice had the ball in the final minutes with a chance to win. The first time, New Orleans stopped backup Jake Locker on fourth-and-1 at the Saints 24 with 2:18 left. The second time, Jo-Lonn Dunbar sacked a scrambling Locker on third-and-goal as time expired.
Brees threw for 347 yards and joined Hall of Famer Johnny Unitas as the only quarterbacks to throw a touchdown pass in 40 straight games.
Locker replaced Matt Hasselbeck, who hurt his left calf in the second quarter.
PATRIOTS 34, REDSKINS 27
At Landover, Md., Tom Brady threw for 357 yards and three touchdowns, and Rob Gronkowski set an NFL single-season record for most touchdown catches by a tight end as New England won its fifth straight.
The Patriots (10-3) again overcame their bend-but-don't-break defense. The Redskins drove to the New England 5-yard line late before Rex Grossman's pass went off Santana Moss' hands and was intercepted by Jerod Mayo with 22 seconds to play.
Washington (4-9) has lost eight of its last nine.
RAVENS 24, COLTS 10
At Baltimore, Terrell Suggs had three sacks and forced three fumbles to keep Indianapolis winless.
Baltimore (10-3) limited the Colts (0-13) to 167 yards — 53 through three quarters. Were it not for a touchdown on the game's final play, Indianapolis would have been held without a TD for the second time since the 2003 season opener.
Joe Flacco threw two touchdown passes and Ray Rice ran for 103 yards and a score to help the Ravens win their fourth straight and improve to 7-0 at home. Baltimore is tied with Pittsburgh for the lead in the AFC North. The Ravens hold the tiebreaker with two wins over the Steelers.
Dan Orlovsky was 17 for 37 for 136 yards and an interception. He was sacked four times.
FALCONS 31, PANTHERS 23
Ryan threw for 320 yards and tied a career high with four touchdowns passing. Atlanta (8-5) avoided a costly loss to stay alive in the NFC wild card race.
For the Panthers (4-8), it was the sixth time this season they've lost after being ahead or tied in the fourth quarter. In October they fell 31-17 to Atlanta despite leading 17-14 going into the fourth quarter.
Cam Newton threw two touchdown passes as the Panthers built a 23-7 halftime lead, but was intercepted twice in the second half.
LIONS 34, VIKINGS 28
At Detroit, backup quarterback Joe Webb fumbled deep in Lions territory in the final seconds, and Detroit escaped with a much-need victory.
Matthew Stafford threw for two scores in the first quarter to give Detroit one of its three-touchdown leads. The Lions (8-5) had lost five of seven, and played without defensive tackle Ndamukong Suh, who was serving the second game of his two-game suspension.
Webb led the Vikings (2-11) to TDs on his first two drives after rookie Christian Ponder was benched.
On first-and-goal from the 1 with 9 seconds left, a replay appeared to show DeAndre Levy grabbing Webb's facemask, but no flag was thrown. The ball popped free at about the 11, and was batted back toward midfield by Detroit's Stephen Tulloch. Webb ran it down and tried to pick it up, but the ball came loose again and Cliff Avril finally fell on it to end the game.
PACKERS 46, RAIDERS 16
At Green Bay, Wis., Aaron Rodgers threw for 281 yards with two touchdowns and an interception in less than three full quarters' worth of work, Ryan Grant had two touchdowns rushing and Charles Woodson picked off a pass against his former team.
With the win, the Packers ran their record to 13-0 — leaving them three games short of completing a perfect regular season. And they did it with a near-perfect performance.
Carson Palmer threw for 245 yards with a touchdown and four interceptions for the Raiders (7-6), who looked like anything but legitimate contenders in the AFC West.
The biggest concern for the Packers was an apparent left knee injury to wide receiver Greg Jennings in the third quarter.
CHARGERS 37, BILLS 10
At San Diego, Philip Rivers threw three touchdown passes, two to Antonio Gates, and the Chargers kept their playoff hopes alive.
Buffalo (5-8) lost its sixth straight game and was eliminated from playoff contention for the 12th straight year. The Chargers (6-7) have won two straight following their six-game losing streak.
Rivers was 24 of 33 for 240 yards. Ryan Mathews gained 114 yards on 20 carries, the first time he's had three straight 100-yard games.
CARDINALS 21, 49ERS 19
At Glendale, Ariz., John Skelton stepped in for the injured Kevin Kolb and threw for 282 yards and three touchdowns, and the Arizona Cardinals rallied to hand the San Francisco 49ers just their third loss of the season.
Larry Fitzgerald had seven catches for 149 yards, including a 46-yarder for a touchdown and a 53-yarder to set up the go-ahead score in the fifth victory in six games for Arizona (6-7).
Kolb left the game after a blow to the head on Arizona's third play. Skelton, benched after throwing three interceptions in the Cardinals' 23-7 loss at San Francisco on Nov. 20, had a 60-yard TD pass to Early Doucet and a 3-yard toss to Andre Roberts for what proved to be the winning score early in the fourth quarter.
EAGLES 26, DOLPHINS 10
At Miami, Philadelphia forced three turnovers while scoring four times during a nine-minute span in the second quarter and totaled nine sacks.
The Eagles (5-8) won for only the second time in the past six games and need a sweep of the final three games to have any chance of repeating as NFC East champions. The Dolphins (4-9) had a three-game home winning streak snapped and sank deeper into last place in the AFC East.
Philadelphia sent quarterback Matt Moore to the sideline in the second half with a head injury.
JETS 37, CHIEFS 10
At East Rutherford, N.J., Mark Sanchez threw two touchdown passes and ran for two more scores as the Jets kept pace in the AFC playoff race.
The Jets got things started quickly by scoring 28 points in the first half and were helped by an inept Chiefs offense that managed 4 total yards in the first two quarters.
Shonn Greene had a season-high 129 yards rushing and a score, and Santonio Holmes and LaDainian Tomlinson each caught touchdown passes for the Jets (8-5), who have won three straight and improved to 6-1 at home.
Tyler Palko was sacked five times for the Jets in a miserable outing by the penalty-plagued Chiefs (5-8), a week after he earned his first victory as a starter against Chicago.
JAGUARS 41, BUCCANEERS 14
At Jacksonville, Fla., Maurice Jones-Drew scored four times, setting the franchise record for career touchdowns, and Jacksonville rolled up 41 unanswered points.
Jones-Drew finished with 136 total yards, including 85 on the ground against one of the league's worst run defenses.
Tampa Bay's bigger problem in its seventh consecutive loss was turnovers.
The Buccaneers (4-9) had seven of them, helping set up each of Jacksonville's four TDs in the second quarter. The Jaguars (4-9), who hadn't scored more than 20 points all season, scored four times in a span of 7:32. They scored on offense, defense and special teams in the same game for the first time since Nov. 1, 1998, at Baltimore.