Updated

There are two ways to look at the plight of five-time NASCAR Sprint Cup champion Jimmie Johnson, who is 20 points behind Brad Keselowski heading into Sunday’s season-ending Ford EcoBoost 400 at Homestead-Miami Speedway.

The pessimistic view: Since 1975, only four drivers have passed the leader to win the championship in the final race of the season. And none trailed as badly as Johnson does now, when you factor the points to reflect equivalent totals from year to year.

The optimistic view: Johnson lost 27 points at Phoenix International Raceway on Sunday, while in the NASCAR Nationwide Series, Elliott Sadler lost 20 points to leader Ricky Stenhouse Jr. on Saturday at PIR. If Johnson can lose that much in one race, he can make that up in one race.

Not surprisingly, Johnson is taking the optimist’s point of view.

“We have nothing to lose and can gamble and take chances,” said Johnson. “Brad doesn’t have that luxury. This isn’t over. This team never gives up and we don’t intend to, now.”

Unfortunately for Johnson, a tire failure at Phoenix left him 32nd in the race and in a big points hole. Now, Johnson not only has to go and win at Homestead, where he’s never won before, he has to hope Keselowski has bad luck or gets caught up in someone else’s mess.

If Johnson wins and leads the most laps on Sunday, Keselowski still takes the championship if he finishes 15th or better and doesn’t lead a lap; 16th and leads at least one lap; or 17th and leads the most laps.

What makes that especially daunting is Keselowski’s relentless consistency. In the last 28 races, he’s finished worse than 15th just twice, coming home 18th at Pocono in June and 30th at Bristol in August.

The rest of the season he’s been pretty much bulletproof. That history strongly favors Keselowski, although it certainly doesn’t guarantee anything.

Despite that, Johnson vows to go all out at Homestead on Sunday. After all, two years ago he came into the final race of the season behind Denny Hamlin and took the championship away.

“My focus is going down there and winning the race,” said Johnson of Homestead. “We typically haven’t had to have that mentality going into this race, but we have shown we can race for the win. We did it in 2010 against Denny, finished second and won the championship. This 48 Lowe’s team can do it again.”

Tom Jensen is the Editor in Chief of SPEED.com, Senior NASCAR Editor at RACER and a contributing Editor for TruckSeries.com. You can follow him online at twitter.com/tomjensen100.