If you look at the entire country, excluding New York City, 4.5 million people work at home, and only 3.7 million take mass transit to work. That's from the Census Bureau's 2005 American Communities Survey, by way of Wendell Cox at the Heartland Institute. He concludes, "Perhaps it is time to think about paying people to work at home rather than paying transit to not carry people."
Ever since the folks at Heartland went on an antiscience crusade I don't quote them without checking the source. Sure enough, Cox is fudging -- not by falsifying the numbers but by aggregating them to support his thesis and by ignoring the fact that many people don't have access to mass transit (most people of course drive to work).
Take the Census Bureau's figures for the seven-county Chicago area: In Cook County 68,000 work at home and 388,000 take transit to work. In Du Page County: 21,000 and 28,000. Will County: 10,000 and 14,000. Lake County, Indiana: 4,000 and 6,000. McHenry County: 6,000 and 6,000.
Cox's thesis is borne out in only two counties. In Lake County: 14,000 work at home and 13,000 take transit. In Kane County: 10,000 and 6,000.
Clearly in Chicagoland, except at the fringes, more people take transit to work than work at home.
Irony alert: if you were determined to pass a uniform transportation policy for the whole country (minus NYC), then Cox's breakdown of the figures would make sense. If you were a sincere conservative or libertarian, believing in local choice and adaptation, you'd be more interested in the numbers given above.