Don't tell Cadillac dealers this is one of the best years ever for luxury auto sales.
Mercedes, BMW, Lexus and Audi are all outpacing the overall growth in auto sales, but Cadillac has the dubious distinction of being the only mass market luxury auto brand where sales are down in the first half of 2014.
"This is a tough time for Cadillac," said Dave Sullivan, an analyst with Auto Pacific. "They're not bad vehicles. In fact, Cadillac is doing the right things. Unfortunately, they are going after the same buyers as the Germans and right now the Germans are very strong."
In particular, Audi and Mercedes-Benz are thriving in the entry level luxury market where the Audi A3 and Mercedes CLA Class have done well in the first half of this year. By comparison, the Cadillac ATS, which has outsold the A3 and CLA individually this year, has seen sales slump 21.8 percent, according to the research firm Autodata.
So why have Cadillac sales slipped 1.2 percent this year?
GM executives say nothing is wrong.
Cadillac still has an average transaction price of over $49,000 and the decision to cut fleet sales of Caddy's to rental car firms and corporations has weighed on overall sales.
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That said, here are a few reasons why other luxury brands are driving past Cadillac when it comes to U.S. sales.
Mercedes, Audi winning entry-level battle
A year ago, the ATS was the engine driving Cadillac sales up 22 percent. It also had far less competition.
At the halfway mark of 2014, the Audi A3 and the Mercedes CLA Class have combined to outsell the ATS.
Some of that may be due to Cadillac CTS customers coming off of their leases and deciding they don't want to pay more to renew a CTS lease.
"People are coming off CTS leases and the new CTS is more expensive so they're moving on or deciding they don't want the ATS which is a smaller car," said Sullivan.
The entry level cars are not the most lucrative luxury models, but it's the segment where automakers are waging a heated battle. Audi has leveraged the launch of the A3 and an ad campaign featuring comedian Ricky Gervais to grow the German brand's overall sales.
In fact, Audi has now passed Cadillac to become the fourth largest luxury brand in the U.S.
Cadillac executives admit the ATS is facing stiffer competition.
"We've never had a product like the ATS," said Dave Caldwell with Cadillac. "We've got credibility growing with entry level cars, but it will take time until we beat the Germans at their game. You have to earn and win over buyers. That's going to take time."
When Cadillac rolled out the extended range electric ELR earlier this year, it was accompanied with an ad campaign featuring an upscale, ultra-confident middle age father who talked about "creating your own luck". The ad ends with him unplugging his ELR before driving off.
GM paid big bucks to run the ad on Super Bowl Sunday.
Did the investment pay off?
This year, Cadillac has sold just 390 ELR models, which start at $75,000.
"Is the ELR a total flop?" asks Sullivan. "Yes. The only people I see driving them are GM employees."
Caldwell downplays slow ELR sales by calling it a niche model.
"The ELR is a very new idea. We have a lot of work to do with it, but this is a car that says to the consumer, 'these guys are up to something'," he said.
Profitable and booming in China
While Cadillac sales may not be keeping up with the competition in the U.S., the brand is widely believed to be very profitable. Officially, General Motors doesn't break down the profitability of its individual brands.
However, analysts point to the fact sales of Caddy SUV's and crossovers are up more than 14 percent. SUV's and Crossovers are among the auto industry's most profitable vehicles.
Sullivan adds that the redesigned SRX and a new, smaller crossover will give Cadillac a shot in the arm when they hit showrooms over the next two years.
"I'm not too concerned about Cadillac," said Sullivan. "It's all about the upcoming battle in luxury crossovers and Cadillac is very strong in that area."
Meanwhile, Cadillac sales are booming in China, where the demand for luxury autos remains red-hot. By the end of the year, Cadillac expects sales in China to jump 40 percent
"China sales will be up significantly, but we're still a niche player in that country," says Caldwell.
As encouraging as China is for Cadillac, the U.S. remains its biggest market. Despite lagging sales this year, Caldwell believes the brand is positioned to rebound.
"We have a cool brand with a strong heritage," he said. "We've graduated to the next level of competition. We have to win head to head when we go up against other luxury brands and I think over time we will."
Questions? Comments? BehindTheWheel@cnbc.com.