According to a study done by Zogby in the May issue of their Econ Journal Watch done on a pool of nearly 5,000 [precisely 4835] participants, those who classified themselves as being liberal or progressive/liberal answered more questions incorrectly regarding fiscal matters than their more conservative counterparts, by a shocking degree to boot. They even scored worse than those who wrote "I don't know." for all of the answers.
"How did the six ideological groups do overall? Here they are, best to worst, with an average number of incorrect responses from 0 to 8: Very conservative, 1.30; Libertarian, 1.38; Conservative, 1.67; Moderate, 3.67; Liberal, 4.69; Progressive/very liberal, 5.26.
Americans in the first three categories do reasonably well. But the left has trouble squaring economic thinking with their political psychology, morals and aesthetics."
...Or they are just intellectually dishonest.