Larry H. Miller, of Sandy, Utah, was eighth with 61,097 new vehicles sold.
Asbury's heightened revenue means "it becomes increasingly difficult" for Lithia to buy the group, agreed Rajat Gupta, an analyst for J.P. Morgan Chase & Co.
Lithia declined to comment for this report.
Asbury would have represented a complementary geographic footprint to Lithia, Jeffries analyst Bret Jordan said. An Asbury with Miller's locations creates more overlap, he said, but Seaport Research Partners analyst Glenn Chin felt Asbury would still appeal to Lithia.
Chin said Lithia could "definitely" still attempt to buy Asbury, though he agreed that Asbury's new size would pose a challenge. Morningstar analyst David Whiston didn't rule out Lithia or another company trying to bid for the larger Asbury.
But Lithia could also just buy dealership groups that fall into the "big, but ... not megabig" category, said Whiston. Those groups would have a tougher time competing with larger brands and might be more amenable to a sale and less expensive for Lithia, according to Whiston.
Finally, there's the question of whether Lithia would "want to go hostile," which can be a distraction, according to Whiston.
Gordon said pairing Lithia with Asbury would create a "merger of equals" scenario.
"Those are really hard to do," he said, saying such mergers are "likely to fail." A successful merger needs a dominant party, Gordon said.
Asbury could merge with other large retailers, he said, such as AutoNation Inc., Penske Automotive Group Inc. or used-vehicle retailer CarMax. AutoNation, of Fort Lauderdale, Fla., and Penske, of Bloomfield Hills, Mich., ranked No. 1 and 2, respectively, on the Automotive News top 150 list. AutoNation sold 249,954 new vehicles in 2020, and Penske sold 178,437.
However, Asbury would represent a "big bite" for any of them and dilute the value of owners' shares if new stock were issued to fund the purchase, according to Gordon. "I don't think anybody's gonna come after them," he said of Asbury. "They've reached that critical mass."