ATLANTA -- They dance and they strut and they create their own handshakes.

They grin and they point and they double over in laughter.

They mug and they hug.

The personality transformation undergone by the 49ers in recent weeks has been striking and there is little doubt much of it is attributed to the midseason installation of Colin Kaepernick as the starting quarterback.

How can this team not get caught in the thrall of a young leader who is exciting, effective and operates with such symmetry between confidence and humility?

How can the 49ers not rally around a tattooed gunslinger who is taking them into the end zone to punctuate offensive drives that previously concluded with field goals?

San Francisco 49ers Quarterback Colin Kaepernick speaks at the 49ers press conference at the 49ers practice facility in Santa Clara, Calif. on Friday,
San Francisco 49ers Quarterback Colin Kaepernick speaks at the 49ers press conference at the 49ers practice facility in Santa Clara, Calif. on Friday, January 18, 2013. (LiPo Ching/Staff) ( LiPo Ching )

The newfound ebullience of the offense was on full display in San Francisco's victory over Green Bay last week and, if the scoreboard allows, will be visible Sunday at the Georgia Dome when the 49ers face the Atlanta Falcons in the NFC Championship game.

Kaepernick's energy radiates through the offensive unit, bringing observers out of their seats and teammates together. It's an altogether different vibe than that which existed under previous starter Alex Smith.

Smith had evolved into a steady, measured leader of the band. Practically every movement followed a rational message from his brain. This businesslike approach obscured his joy, rarely allowed for a spontaneous burst of excitement.

Alex could gather the troops. He could show them the way and they would follow.

But the 49ers feel Kaepernick.

"He's a guy that gets excited," center Jonathan Goodwin says. "He's a confident guy. Guys feed off things like that, when you have your quarterback celebrating and doing things like that."

Beneath Kaepernick's veneer of seriousness is a conspicuous passion, which sets an inviting, engaging tone. It's not unlike the way the Green Bay Packers used to respond to the unbridled glee of future Hall of Famer Brett Favre. Kap's effect on the Niners' offense has been nothing short of galvanizing.

There is a level of brotherhood within the unit that compares to that which the defense has enjoyed since the middle of last season.

If a receiver or a running back scores, you'll see Kaepernick, sprinting toward him for a celebration. If Kap scores, you'll see running backs and receivers and lineman hustling over to share the touchdown moment.

This quarterback revels in his success, and his teammates revel with him.

"He's amazing," guard Alex Boone says.

Ask running back LaMichael James about Kaepernick and the rookie smiles and shakes his head.

"You never know what you're going to get," James says, "but you're probably going to like it."

At 25, Kaepernick is made for the Now Generation, a biracial physical specimen with hip-hop swagger, abundant tatts, a keen intellect and extraordinary athletic gifts. He is part of the NFL's new breed of quarterbacks, which include Carolina's Cam Newton, Washington's Robert Griffin III, Indy's Andrew Luck and Seattle's Russell Wilson.

These talented tyros don't just play the position; performance and the sheer force of their personality grant them command. After eight NFL starts, Kaepernick is dramatically reshaping the identity and personality of the 49ers offense. It's his offense.

"They have handshakes and all kinds of stuff, like flexing," Goodwin says. "But the guys are responding and getting even more excited. He's bringing some excitement to this team."

Suddenly, there is an unmistakable camaraderie in the huddle and along the sideline, where Kaepernick may sidle up to any teammate, at almost any time, for a conversation that almost always looks like fun.

After racing in for a 56-yard touchdown to finish off the Packers eight days ago, Kap went over to the sideline and leaned over rookie receiver A.J. Jenkins, who was seated on a bench, and challenged him to a footrace.

"He's one of the guys," tight end Vernon Davis says.

"Kap's just doing his thing," running back Frank Gore says.

"He's having fun in the game," Randall Cunningham, one of Kaepernick's idols, observes from his home in Las Vegas. "He's not anxious. He's like a little kid. That's what we need to see more of, and this generation -- Kap, RGIII, Luck, Wilson -- these guys are stepping right in."

Moreover, the 49ers are stepping along with Kaepernick, who is rapidly filling the pop-culture vacuum left by the invisibility/irrelevance of Jets backup Tim Tebow.

There are a couple differences, though. Whereas Tebow often drops to one knee and bows his head as if in prayer, Kaepernick is more likely to flex his muscle and smooch his bicep. And Kap is a much better quarterback.

He has the 49ers, as a team, exactly where they were at this time last season. But the offense is tighter and brings more swag to the show. These guys are edgy, they're loose and they're enjoying the stage.

Contact Monte Poole at mpoole@bayareanewsgroup.com. Follow him on Twitter at twitter.com/1montepoole.