When we first saw and drove new midsize sedans like the 2013 Nissan Altima and 2013 Ford Fusion, we had a feeling the Toyota Camry would eventually see a challenge for the top sales spot, but we had no idea things would move this quickly. Automotive News is reporting that the quarter tallies still show the Camry holding a sizable lead over its competition, but the Altima did manage to outsell the Toyota by 100 units last month. While a single month of not outselling the competition might not be enough to unseat the Camry from its 11-year sales throne, it goes to show how far recent competitors in the segment have come.

The four best-selling cars in the midsize segment (in order) are the Camry, Honda Accord, Altima and Fusion, with each car boasting more than 80,000 units through the first three months of the year. Both the Accord and Fusion are seeing double-digit year-over-year sales increases while the Camry and Altima have dropped somewhat. And it wasn't just Camry that was losing ground. As we saw in the March 2013 By The Numbers post, Toyota sales as a whole were down slightly from 2012 while all of its key competitors (Chevrolet, Ford, Honda and Nissan) were in the green.

After the top four sellers in the segment, the next closest midsizers are the Chevrolet Malibu and Hyundai Sonata, but these cars are well off the competitive pace. Although the 2014 Mazda6 isn't expected to take too big of a bite out of the midsize market, its attractive design and available diesel engine could continue the shakeup of this once-predictable segment.