What do you do if you want to promote your latest high-MPG offering to consumers?

You could report the model's official EPA figures, if you think they look good enough. Or, if you're Kia, you send two professional drivers on an 8,000-mile, 48-state journey around the U.S. and report their spectacular gas mileage.

The number? 64.5 mpg, which sets a Guinness World Record for the highest mpg for a drive through the contiguous 48 states. Quite a specific record then, but a record nevertheless.

The drivers, Wayne Gerdes and Chris Bernius, actually set their record last year, having set off from West Point, Georgia, on August 26 2011. On the 7,899-mile route, they used less than 123 gallons of gas.

Early on in the drive, the pair were averaging as much as 69 mpg using 'hypermiling' techniques, but 64.5 is still a number to be proud of--as demonstrated by Kia's new tongue-in-cheek advert for the 2012 Optima Hybrid.

It's certainly more than the 35 mpg city and 40 mpg highway given to the model by the EPA, already impressive for a midsize, 206-hp sedan.

Kia said earlier of the record, "It has been specifically designed to achieve maximum fuel economy in all driving conditions, not just in the city... [it] is the ultimate 'real-world' challenge".

What sort of gas mileage do you get from your own hybrid? Let us know in the comment section below.

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