By JANIE McCAULEY
AP Sports Writer
SAN FRANCISCO (AP) - Aldon Smith's high-flying defense gave Colin Kaepernick all kinds of extra chances in his first career NFL start.
And the Kaepernick looked little like a backup in delivering on nearly every one of those opportunities under the lights on football's big stage.
The strong-armed Kaepernick passed for 243 yards and two touchdowns in place of the injured Alex Smith, Aldon Smith had 5½ sacks, and the 49ers whipped the Chicago Bears 32-7 on Monday night in a highly anticipated NFC showdown that hardly lived up to the hype.
"I wanted to come out and show what I'm capable of and show that I can be a starter," Kaepernick said. "That's what I've been trying to prove since I've been here."
With Aldon Smith wreaking havoc on the other side of the ball, Kaepernick threw touchdown passes to Vernon Davis and Michael Crabtree, and Kendall Hunter ran for a 14-yard score as San Francisco (7-2-1) jumped out to a big lead by scoring on each of its first four possessions.
Jason Campbell, the other quarterback in this matchup of backups for division leaders, threw a 13-yard touchdown pass to Brandon Marshall in the third quarter, but was sacked five times and threw two interceptions in his first start since October 2011 for Oakland.
He faced fierce pressure all night, playing for the Bears (7-3) while starter Jay Cutler recovers from a concussion suffered eight days earlier - just like Alex Smith.
After Kaepernick's stellar night on national TV, there's certain to be chatter of a quarterback controversy for the NFC West-leading Niners. And anyone who knows coach Jim Harbaugh knows he's all about competition - at every spot on the field.
"I usually tend to go with the hot hand, and we've got two quarterbacks with hot hands," he said. "We'll make that decision when we have to make it."
Kaepernick certainly isn't counting on it.
"I don't think one game can be called a hot hand," he said.
Aldon Smith took over the NFL sacks lead with 15, passing Denver's Von Miller with 13, and recorded the second-best total in franchise history behind Fred Dean's six-sack day on Nov. 13, 1983, against New Orleans. Tarell Brown and Dashon Goldson each had an interception for San Francisco's stingy defense, which shut down Campbell, Matt Forte and Co. three years after the teams last met in a 10-6 49ers home win.
"I think I have a thing for night games, I love playing at night," Smith said. "I love playing under the lights."
Kaepernick, Aldon Smith and Hunter sure made general manager Trent Baalke looked good for his selections from the 2011 draft class.
"Colin is the man!" Davis said emphatically. "Colin did a great job, I was very proud of him."
And reigning NFL Coach of the Year Harbaugh earned a key victory four days after his own health issue. The 48-year-old Harbaugh had a minor procedure for an irregular heartbeat Thursday.
The 49ers added a safety in the fourth quarter after a replay review. With 9:24 left, former San Francisco offensive lineman Chilo Rachal was called for intentional grounding out of the end zone, but Harbaugh challenged and the review showed Rachal's knee was down in the end zone before the ball left.
"Tonight was probably the worst nightmare. We just have to find a way," Campbell said. "It's one game that we lost. We have to pick it back up next week and try to get back on the winning side. Our goals and everything still sit ahead of us."
The soft-spoken, stone-faced Kaepernick went 16 for 23 with a 133.1 passer rating. He completed 12 of his first 14 passes with a 57-yard strike to Kyle Williams that set up Davis' 3-yard TD on the next play - and he already had amassed 126 yards passing by the end of the first quarter.
The 49ers led 17-0 on Hunter's early TD run in the second, quickly topping the 14.8 points the Bears were allowing per game.
Kaepernick threw for 184 yards in the first half alone - an impressive outing for the second-year pro selected in the second round out of Nevada.
"I think after the first drive I felt really comfortable with what they were doing and what we had in our game plan," he said. "I really wasn't too nervous. I've had a lot of time in this offense. My teammates were really supportive."