Published: May 18, 2014 10:28 AM EDT

BALTIMORE (AP) - It gets even harder from here on out for California Chrome.
    
He won easily in his home state of California, he dazzled in the Kentucky Derby and he dug deep to win the Preakness on Saturday.
    
Now comes the toughest test of all, the Belmont Stakes in three weeks.
    
The chestnut colt with four white feet will attempt to sweep the Kentucky Derby, Preakness and Belmont, something that hasn't been done since Affirmed in 1978. Since then, 12 horses have won the first two legs and failed to complete the sweep in the 1 ½-mile Belmont; the last was I'll Have Another, who was scratched on the eve of the Belmont two years ago.
    
"You have to have a very good horse to win these three races," said Art Sherman, the winning 77-year-old trainer. "I'm hoping I've got one right now."
    
Maybe the horse with the modest pedigree and average Joe owners is the one.
    
California Chrome defeated Ride On Curlin by 1 ½ lengths in the Preakness, covering 1 3/16 miles in 1:54.84 on a sunny and cool day at Pimlico.
    
He's now won six straight races. The streak started with four in a row in California by a combined 24 ¼ lengths. Then California Chrome coasted home in the Derby by 1 ¾ lengths after opening up a big lead in the stretch. The margin dwindled in the Preakness as he fought off multiple challengers.
    
California Chrome's co-owner Steve Coburn shed tears after his colt crossed the finish line, dabbing them away with a blue-and-white bandanna.
    
"I don't mean to be bold or cocky or arrogant," Coburn said. "I saw this baby when he was a day old, I told my wife, 'Carolyn, this horse is going to do something big. I don't know what it is, but we're going to stay in the game to make sure this colt gets to be the best that he can be.'"
    
Quite a statement from a guy with a one-horse stable.
    
Coburn and partner Perry Martin bred an $8,000 mare to a $2,500 stallion to produce California Chrome. Based on the colt's humble breeding, he probably shouldn't be on the verge of making history.
    
His mother, named Love the Chase, won just one race.
    
The owners were long shots to get this far, too.
    
Coburn and Martin named their operation DAP Racing, which stands for Dumb Ass Partners. Their silks include an image of a donkey. Coburn and Perry who live on each side of the California-Nevada border get up early for their jobs - Coburn working as a press operator and Martin running a lab that tests high-reliability equipment.
    
"We just hope that this horse is letting America know that the little guy can win," Coburn said.
    
Sent off as the overwhelming 1-2 favorite by a record crowd of 123,469, California Chrome bounced out of the gate running, with jockey Victor Espinoza moving the colt into the clear. Pablo Del Monte, a 34-1 shot, charged to the lead and was soon joined by filly Ria Antonia.
    
Espinoza tucked California Chrome into third, an ideal spot behind the leaders. They stayed there until making their move approaching the final turn.
    
"I had to move early today," Espinoza said. "I had to start moving at the half-mile pole, which is tough for a horse to start moving early and keep going all the way to the end. California Chrome proved he can move."
    
California Chrome went for the lead, catching Pablo Del Monte while Social Inclusion joined the chase. Pablo Del Monte soon dropped back along the rail, and California Chrome sprinted away from Social Inclusion at the top of the stretch.
    
But there was one more challenge to come.
    
Ride On Curlin, next-to-last in the 10-horse field, ranged up and briefly appeared ready to overtake California Chrome. Once again showing his class, California Chrome denied the threat.
    
"It's an awesome feeling," Espinoza said. "Today it was just a crazy race. I got more tired mentally than physically. I see another horse go to the front. I was going to sit second. ... I sit back, as soon as the other horse got clear of me, it worked out perfect."
    
California Chrome paid $3, $3 and $2.40. Ride On Curlin returned $5.60 and $3.80, while Social Inclusion was another 6 ½ lengths back in third and paid $3.40 as the 5-1 second choice.
    
General a Rod was fourth, followed by Ring Weekend, Pablo Del Monte, Dynamic Impact, Kid Cruz, Bayern and Ria Antonia.
    
Espinoza will get another crack at trying to complete the Triple Crown, after missing with War Emblem in 2002. He finished eighth in the Belmont that year.
    
"You have to be a super horse to win," the jockey said. "Hopefully, California Chrome comes back good, and he's the one that hopefully can do it."
    
Bob Baffert trained War Emblem, one of his three Triple tries that ended in failure. He missed with Silver Charm in 1997 and again the following year with Real Quiet, who lost the Belmont by a nose.
    
"California Chrome is something. He's a cool customer," Baffert said after the race. "He does everything right. He's fast enough to stay out of trouble."

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