Toyota announced today that it had sold its one millionth Prius in the U.S. It's a big milestone for the Prius, an electric hybrid that first came to American markets in 2001. The Associated Press writes that what was "once viewed as a science experiment for environmentalists... has become a mainstream vehicle in the United States." But it wasn't always clear that the Prius would become a success story--here's a look at some of the struggles it's faced.

Image problems. From the start, the Prius carried certain unflattering associations: people who drove it were nerds, or out-of-touch coastal liberals. In 2002, The Washington Post ran a trend piece about how much Hollywood types love their hybrids; the Prius was name-checked repeatedly. A 2006 episode of South Park saw one character buying a "Toyonda Pious"--a hybrid car whose drivers emit clouds of air pollution called "smug." Last year, Dan Akerson, CEO of GM, called the Prius a "geek-mobile" and said he "wouldn't be caught dead" in one. And there were a certain number of people who didn't seem at all sad when Toyota recalled about half a million hybrids in 2010.

Toyota's terrible late-'00s period. Speaking of recalls, it's worth remembering that Toyota has had an absolutely catastrophic time of it lately. 3.8 million recalls for floor mats. 1.4 million recalls for seat belts and exhaust pipes. 1.7 million recalls for fuel lines and fuel pumps. 2.1 million more recalls for floor mats. And that's just going back to 2009. It got so bad that at one point, NASA was called in to make sure radiation from outer space wasn't screwing things up.

Disruptions from the Japanese earthquake. Last month's earthquake scrambled industrial output in Japan, causing Toyota to shut down several factories temporarily. This, in turn, has given the company a financial black eye: Moody's is said to be considering a downgrade of Toyota based on "the likely financial impact" from the earthquake, reports The Wall Street Journal.

One million cars in 10 years isn't exactly a runaway success--for the sake of comparison, Toyota sold between 200,000 and 400,000 Corollas in the U.S. almost every year during the same period. But fortunately for the Prius, gas prices have been creeping higher and higher since the start of 2011--meaning the demand for hybrids isn't likely to flag any time soon. Maybe that's what finally put the Prius over the one-million mark. Or, maybe it was that contest where participants tried to break the world record for draping slices of Swiss cheese over someone's face in a Prius. As the Prius has long been as much a cultural item as a car, you never know.