A steady cadence of new advertisements during key events made March the best month for GMC Hummer EV reservations since the SUV version was unveiled a year ago.

"Awareness is a big thing, and I think that is on our side," said Duncan Aldred, global VP of Buick-GMC.

GMC during the NBA All-Star Game in February debuted a commercial that showcased the electric Hummer pickup's four-wheel-steer "crabwalk" feature with LeBron James. Another James-narrated spot featuring the Hummer SUV's performance and specs ran during the NCAA college basketball tournament.

"Every time we seem to just put a little bit of an awareness tweak out there ... we see the reservations follow," Aldred said.

GMC has logged more than 66,000 reservations for the Hummer pickup and SUV.

Before the SUV goes on sale next year, the brand plans to replicate the media push it applied to the pickup.

"We haven't seen how high the ceiling is," said Matt Mallino, marketing and advertising manager for the Hummer. "I don't know if there is one, quite frankly."

As GMC goes through the Hummer product life cycle, the brand will highlight special editions, colors and over-the-air updates, Aldred said. "We'll keep the drumbeat going."

Beginning customer deliveries also helped propel reservations last quarter. GM delivered 100 Hummer pickups from December through March. Knowing the vehicle is available has heightened interest, and customers are taking note of the Hummer's resale value. Some of the pickups have resold for more than double their original price of nearly $113,000.

"The more you think you can't have something, the more you want it," Aldred said.

Will Churchill, co-owner of Frank Kent Motor Co. in Arlington, Texas, said many of the reservation holders he knows owned the gasoline-powered trucks of the Hummer brand that GM discontinued in 2010.

"GM did a great job by bringing it back, and you can tell by the excitement generated around it," Churchill said.

"It's a vehicle that garners a lot of emotion. And once you've had one, you're just kind of always a Hummer person."

Howard Drake, dealer principal at Buick-GMC Sherman Oaks in Southern California, hopes that GMC uses the Hummer as a flagship for the brand in its broader advertising. Hummer demand is booming, so there is little need to feature the truck in every ad. But awareness of the Hummer will benefit GMC as a whole, he said.

"If you look at TV shows, [Mercedes-Benz] G-Wagens are pervasive. The placement that G-Wagens have in movies and TV shows is crazy," Drake said. "I think that the Hummer can be our G-Wagen."