The Ford Fiesta has become a serious player in the Ward’s Lower Small car segment, beating key rivals, including the Toyota Yaris, to the 35,000-unit mark this year.

Fiesta deliveries in May tallied 7,120, outpacing the segment-leading Nissan Versa, which saw 4,793 deliveries. Year-to-date, the Versa is 4,947 units ahead of the Fiesta, but the gap is closing rapidly.

The Fiesta’s share of the segment skyrocketed from just 4.6% in June 2010 – its U.S. launch – to 29.1% through April, according to Ward’s data.

Ken Czubay, vice president-U.S. marketing, sales and service, says the car should continue to control well over 20% of its segment through May.

While high fuel prices played a part in the Fiesta’s success, there were additional factors at play, Czubay says.

“Fiesta customers are up to three times more likely to buy for style and innovation in this segment,” he says in a conference call with market analysts and the media.

“Eighteen percent of Fiesta buyers are buying for the first time, and the average (customer) age is younger than (those of the) two of the well-known nameplates in the segment,” Czubay says, declining to reveal the models.

The auto maker is quick to quash speculation Fiesta sales likely were boosted by a shortage of Japanese vehicles resulting from the March 11 earthquake.

George Pipas, Ford’s top U.S. sales analyst, says the company has been getting increased consideration from small-car buyers over the past year.

The new ’12 Focus C-car had a strong showing in its first full month on the market, racking up 22,303 deliveries, nearly on par with the new Chevrolet Cruze (22,711).

The Focus’ retail share of the C-segment increased to 9% for the month, up from 6% in April, Czubay says.

While gasoline prices helped the B- and C-segments, they put the brakes on fullsize truck sales, including Ford’s venerable F-Series pickup, which saw demand drop 10.5% to 39,450 units, the first decline from year-ago in 17 months.

Fuel prices also led to a dramatic mix shift in F-Series sales, Czubay says.

“For the first time in decades, V-6s outsold V-8s with the F-150,” he says, noting 55% of buyers chose either the 3.5L direct-injected turbocharged V-6 EcoBoost engine or the 3.7L V-6.

“It’s one of those ‘Ripley Believe It or Not’ moments,” Czubay quips. “Who would’ve thought?”

Strong small-car sales negated the drop in truck deliveries, as Ford’s total May sales rose 7.6% to 188,580, based on 24 selling days this year vs. 26 in like-2010.

Ford’s retail sales were up 5%, while fleet deliveries were down 8%, Pipas says.

The auto maker ended the month with 397,000 vehicles in stock, including 103,000 cars and 294,000, amounting to a days’ supply in the low 50s.

Ford says it will produce 630,000 light vehicles in the third-quarter, consisting of 225,000 cars and 405,000 trucks and cross/utility vehicles, marking an 8% increase from year-ago.

bpope@wardsauto.com