FORTUNE -- Ford Motor Company can't be faulted for bragging that it sells more of a single car model, the compact Ford Focus, than any automaker in the world -- even if the claim is debatable, given Toyota's rebuttal that its Corolla compact is the true champ.
The number of cars separating the two models isn't that large. Which one sold more probably relates to model-naming nomenclature and to scorekeeping convention, arcane subjects of little interest to anyone but automotive marketing executives.
Besides, the key point is that Ford (F) finally -- and importantly -- has figured out how to build and market a world car. That proficiency, which eluded Ford for decades, is what helped make Toyota (TM) a powerhouse and reap the financial benefits from vast efficiencies of scale.
Auto executives like to brag about market leadership for two reasons: The claim that your model is the best-sellerin a particular category could attract others to buy it for just that reason. Second reason: Hubris. "Trash talking and egos run amok," said one auto executive who declined to be identified. "Biggest shouldn't be the goal for any automaker, and you shouldn't have to sell your soul to get there, for example, big incentives" and discounts to move cars at little or no profit.
According to R.L. Polk, which tracks registrations in 80 countries globally, Focus notched sales of 1,020,412 in 2012. Erich Merkle, Ford's sales analyst in Dearborn, Mich., said "it's a testament to our product, to the large number of people who are interested in Focus. We don't do everything to sell every last vehicle we can, we want owners to be passionate."
The current model is in its third generation and for a time shared the name with a European version that was a different vehicle. That strategy changed following the arrival of Alan Mulally as CEO in 2006, who insisted on a "One Ford" approach to take advantage of global scale whenever possible.
Mulally's strategyhas worked brilliantly so far, leading to vast improvements in Ford's operating and financial results. Merkle points out that naming the car the same in all markets recognizes that global commerce means a Chinese business woman might well rent a Focus on a trip to the U.S. -- and look for it when she returns home.
Toyota, according to Mike Michels, a spokesman in Torrance, California, sold 1.16 million Corollas worldwide in 2012 -- which would seem to make Corolla the best-selling compact car. But R.L. Polk numbers fail to reflect 300,000 Corolla sales, he said, for reasons that haven't been clarified.
He acknowledges that some vehicles Toyota counts as Corolla might be counted as separate models in some countries, such as Corolla Axio and Corolla Altis. He says "Axio" and "Altis" are like SE and SL designations in the U.S., an indicator of trim level, i.e. what features are included.
In a statement released by Anthony Pratt, vice president of forecasting for R.L. Polk, the company said "Polk data reported by Ford earlier this week is accurate based on the single nameplate Ford Focus." He also said the data is compiled from 80 countries; Toyota says its Corolla is sold in 130 countries.
Neutral analysts agree that Focus has been a home run for Ford, with strong critical reviews as well as global appeal among buyers. Likewise,the Corolla's enduring appealsymbolizes Toyota core strength, helping it to rebound from a variety of quality, legal, and political difficulties – not to mention the 2011 tsunami.