I think there is the idea that to be a liberal, one must be poor, or at least not very wealthy. there are certainly those(the very wealthy) who talk a good liberal game, but do very little to support the cause. Those would be a "Lexus Liberal". There are also those who do very well financially(enough to afford a Lexus), that give both of time and money to promote social and environmental causes associated with being liberal.
I think the phrase is quite apt, though I would guess that most Lexus owners don't fall under the liberal moniker anyway...



formerly known as etaoin...