LOUDON, N.H. -- Jimmie Johnson proved to be an expert fuel strategist Sunday, conserving his gas to win at New Hampshire International Speedway in a race that widened Matt Kenseth's hold on the Winston Cup points standings.

Johnson took the lead with 37 laps to go in the New England 300 and kept a close eye on his fuel gauge to make sure he had enough to hold off Kevin Harvick at the finish in a battle of Chevrolets.

''I think some strategy played into it at the end with us pitting at the last minute and gambling we had enough gas to finish it,'' Johnson said. ''After I took the lead, I had to look in my mirror the rest of the way while I conserved fuel and kept an eye on whoever was second. But I was able to ride around and watch my gas and we made it.''

Kenseth -- also cutting it close on gas -- finished third to extend his lead in the championship race to a whopping 234 points over Jeff Gordon. It's Kenseth's largest margin since he took over the lead in early March.

Ryan Newman finished fourth in a Dodge, and Robby Gordon was fifth in a Chevrolet.

Dale Earnhardt Jr. ended up sixth and maintained the third spot in the points standings. But Earnhardt is now 273 behind Kenseth.

Gordon, who easily had the best car for most of the day and led a race-high 133 laps, finished a disappointing 24th.

Dale Jarrett finished seventh and Steve Park was eighth -- putting all three of Richard Childress Racing's cars (Harvick and Robby Gordon) in the top 10 for the first time this season.

Roush Racing teammates Jeff Burton and Greg Biffle rounded out the top 10.

The field was set by points after rain washed out Friday's qualifying, putting Kenseth, Jeff Gordon and Earnhardt up front at the start. Johnson began sixth, but quickly moved into second and was racing for the lead soon after.

Drivers then jockeyed for track position over many of the race's 12 cautions, with some pitting for gas and tires and others staying out to pick up spots.

When caution came out with 96 laps to go, about 15 cars decided not to pit. Harvick and Johnson did, gambling that would be the last time they would have to stop for gas.

Kenseth came in under that caution, too, boosting his chances of getting to the end without a stop.

But the 12th caution came out with 66 to go when Christian Fittipaldi hit the wall. So the 15 cars that didn't stop under the previous caution went in for gas.

Jeff Gordon was one of them, stopping to take four tires and coming back onto the track in 28th position.

Newman, who used fuel mileage to win last week in Chicago, inherited the lead. Johnson was fifth at the restart.

It didn't take Johnson long to get up on Newman's bumper and with 37 laps to go, he took over the lead with a pass in the first turn. From there it was just a matter of conserving the fuel and hanging on for his second win of the season, fifth of his career.