How to sell car insurance with a wink

Why do I find this Progressive ad so effective? Unlike most commercials, this one has so much "stickiness" that I watch it every time it comes up.

First the aesthetics draw me in. Beautifully shot. A sweet romantic moment with Flo. Then the pivot to selling insurance is done with the perfect touch of humor. Brilliant writing. The message is: "I'll always be there for you." This commercial is targeted to women. It's not the mayhem approach that Allstate uses. But I do wonder, is the soft touch in this commercial as effective as Allstate instilling the fear of mayhem if you pick the wrong insurance company?

Interesting side note: This week's Time magazine (Feb. 4, 2013 edition) featured  an article that mentioned commercials for car insurance and phone service. Did you know only 2% of us ever switch insurance companies and carriers? The major role of advertising in these industries it to keep you. Flo does so in this commercial.