Harvick, who ran away with the 2006 NASCAR Busch Series title, started the season with his 27th Busch victory. This time, he was driving for Richard Childress, who also fields his Nextel Cup Chevrolets.
"Any time you can win any race at Daytona it's big," said Harvick, who will start 34th in Sunday's Daytona 500.
Saturday's race was overrun with Buschwhackers _ Nextel Cup regulars moonlighting in the junior series _ and Harvick controlled the last half of the 120-lap event.
Starting 31st in the 43-car field, Harvick crossed the finish line about three lengths ahead of runner-up Dave Blaney, who gave Toyota a solid finish in its first Busch event.
"I said if we ever get all the way to the front, we're going to be in really good shape," said Harvick, who led the final 42 laps. "Because the whole last run, once I got to the front, I never had to let off the floor."
It was an auspicious start for Harvick, who won nine races last year to earn his second Busch Series title. He beat runner-up Carl Edwards by 824 points.
Even with only a partial Busch schedule planned this season, Harvick's win was no surprise _ he finished in the top eight, including a trio of runner-up finishes, in his nine previous Busch starts on the 2.5-mile Daytona oval.
Still, Harvick's not considering adding more Busch races.
"Absolutely not," he said. "We're here to win races, and it's something to where we just want to go out and hopefully keep going where we left off last year.
"It's just a lot of fun to drive when the car is like that."
Blaney, who will drive one of four new Toyotas in the 500, was involved in a multicar crash on the fourth lap but came away without much damage.
"We just kind of hung around, hung around," he said. "And right at the very end I snuck into second."
Blaney never challenged Harvick.
"Kevin was handling a little bit better than I was, and I couldn't get to his back bumper," he said.
Cup drivers finished in the top 12 spots and had 15 of the top 20, with Edwards third, followed by Clint Bowyer, Mark Martin, Martin Truex Jr., Dale Earnhardt Jr., Tony Stewart, Denny Hamlin, Greg Biffle, Robby Gordon and Matt Kenseth, all entered in Sunday's race. The top Busch regular was Scott Wimmer.
Stewart, the 500 favorite after winning last Saturday's Budweiser Shootout and a 150-mile qualifying race Thursday, saw his string of three straight wins in this race end.
"I got three top 10s in a row, so I'll find the bright side to it," Stewart said.
The 300-mile race was relatively clean, with three caution flags, including two crashes. But the second wreck was a big one, taking out Cup regulars Kasey Kahne, Reed Sorenson, Jamie McMurray and damaging the cars of Cup driver Ward Burton and Busch regular John Andretti, who both finished in the lower half of the field.
It was what has become a typical race at Daytona and Talladega, the two NASCAR tracks where carburetor restrictor plates are used to slow the cars. There was a lot of two- and three-wide racing, and cars moved from the back of the field to the front relatively quickly.
The race had 16 lead changes among 10 drivers.
Kyle Busch, another Cup star, dominated early in the race, leading 46 laps before a fuel pressure problem ended his day.
The two Indianapolis 500 winners in the field, both new to stock car racing, looked good for a while before encountering trouble.
Juan Pablo Montoya, making the switch from Formula One to NASCAR and a starter in Sunday's Daytona 500, drove from 16th to fourth in the early going before his engine blew and relegated him to 40th. Sam Hornish Jr. was running in the tp 20 before bouncing off the wall. He continued but wound up 31st.