Brad Keselowski captures his first Sprint Cup championship

HOMESTEAD, Fla. — Brad Keselowski's astronomically fast rise through the ranks of NASCAR is now complete. On Sunday, Keselowski completed a triumphant season by holding off Jimmie Johnson to win his first Sprint Cup championship.

Keselowski entered the season riding momentum from last year's surprise rise into a Chase wild-card spot, but it took him exactly half a race to prove he would be a center of attention all year long. While Daytona International Speedway burned as a result of a track fire, Keselowski pulled out his phone and began tweeting in the middle of the Daytona 500. Within hours, he'd gained tens of thousands of followers and given NASCAR more publicity with one tiny phone than it could get with a hundred cameras.

Throughout the rest of 2012, Keselowski also proved that he could run strong at every kind of track: short, superspeedway, cookie-cutter, road. He stared down challengers on and off the track, most notably Johnson. The five-time champion appeared primed for No. 6, and in past years he could have counted on challengers wilting in the Florida heat.

Not this time. As the Chase wore on, Keselowski shed his public, freewheeling Twitter persona in favor of a relentless focus. Johnson couldn't rattle him, either on the track or in press conferences, and that dedication and mindset paid off in a championship.

"I saw this really cool video that Ray Lewis did and he said, 'Throughout my whole life I've been told that I'm not big enough, I'm not fast enough, I'm not strong enough and I don't have what it takes,' " Keselowski said after getting out of his car. "I've used that as a chip on my shoulder that's carried me through my whole career. It took 'til this year for me to realize, they're right. I'm not big enough, fast enough, strong enough. No person is. Only a team can do that. And these guys up here [pointing to his team], they make me big enough, fast enough, strong enough to do anything we want to do."

Despite Keselowski entering Sunday's season finale at Homestead-Miami Speedway with a commanding 20-point advantage, there was a stretch of drama. Chad Knaus, Johnson's crew chief, made a gamble on fuel that would have put the No. 48 in a position to win the Ford EcoBoost 400 and potentially wrestle away the points lead from Keselowski, who would have pit twice to Johnson's once. But on Johnson's final pit stop his crew hung a lug nut, resulting in a penalty that meant his quest for No. 6 was all but over. Moments later, when smoke filled his cockpit, it was. Johnson steered his car to the garage, his engine dead, as well as his championship run.

"Pretty heartbreaking," Johnson said moments after Keselowski crossed the finish line 15th to clinch the title. "We were doing what we needed to do, certainly in a position to put a lot of pressure on the 2 car. But that's racing."

The victory has resonance beyond Keselowski. This marks the first-ever Cup title for legendary car owner Roger Penske, and the final (for now) championship win for Dodge, which is leaving NASCAR after this year.

Over the 10 Chase races, Keselowski averaged an impressive 6.3 finish. For comparison, last year Tony Stewart won with the same 6.3 average finish. In other words, this wasn't a Chase that Jimmie Johnson lost with a wreck last week at Phoenix or even a blown engine in South Florida; this was a Chase that Brad Keselowski won with outstanding performances in 10 straight races.

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