Annie Lowrey speculates:
Based on Census Bureau data, five senators would represent Americans earning between $100,000 and $1 million individually per year, with [2/10 of a senator] working on behalf of the millionaires. Eight senators would represent Americans with no income. Sixteen would represent Americans who make less than $10,000 a year, an amount well below the federal poverty line for families. The bulk of the senators would work on behalf of the middle class, with 34 representing Americans making $30,000 to $80,000 per year. . . . Or how about if senators represented particular demographic groups, based on gender and race? White women would elect the biggest group of senators -- 37 of them, though only 38 women have ever served in the Senate.
I don't know how well all of this would work in practice--for one thing, I wouldn't want the senator who represents two-year-olds to be anywhere near the nuclear button--but I agree that ideas of fairness and political representation are subtle.
Along similar lines, here is my response to economists who complained that there were not enough economists in elective office:
I was curious about this so I looked up some statistics--not on Congress but on the workforce. According to the 2001 Statistical Abstract of the United States, there were 139,000 economists employed in the United States, which represented 0.1% of the employed population. 1% of 535 is about 1/2, so with at least two economists in Congress, the profession is hardly unrepresented.
139,000 is a crude estimate because it presumably represents the people whose job title is "economist" (and thus wouldn't include, for example, Matt Kahn, who originally raised the "not enough economists in Congress" issue and whose job title is "professor"). But, even throwing in all these economics professors and various other practicing economists, I still don't think it would add up to the half-million that would be necessary to reach 2/535 of the employed population.
This is not to debate the merits of the argument--perhaps Congress would indeed be better if it included more economists--but rather to note that people with this sort of job are a small minority in the U.S. (In contrast, there were 720,000 physicians, 170,000 dentists, and 2.1 million nurses, and 1.7 million health technicians in the U.S.)
To put it another way, without reference to economists (or to the 2.1 million "mathematical and computer scientists" out there): the Statistical Abstract has 260,000 psychologists. Certainly Congress would be better off with a few psychologists, who might understand how citizens might be expected to react to various policies.
I'm willing to believe that the country's 890,000 lawyers are being overrepresented, but what about the 114,000 biologists? A few of these in Congress might advance the understanding of public health. And then there are the 290,000 civil engineers--I'd like to have a few of them around also. I'd also like some of the 280,000 child care workers and 620,000 pre-K and kindergarten teachers to give their insight on deliberations on family policy. And the 1.1 million police officers and 340,000 prison guards will have their own perspectives on justice issues.
So I think that representation is a tricky issue. Most of us would probably like more "people like us" in Congress, but that's tough with only 535 seats to go around, and given that there are a lot of politicians already out there (many of whom are lawyers) who you'd be competing with.
Does it make a difference? Maybe so. In his article, "Does the Numerical Over-Representation of the Upper Class in U.S. Legislatures Matter?", Nicholas Carnes finds:
Throughout America's history, most political decisionmakers have been highly-educated, wealthy individuals from prestigious, high-paying occupations. . . . On balance, this study's findings suggest that the numerical over-representation of affluent Americans in elected offices promotes more conservative economic policy outcomes, although not for the straightforward reasons that political observers have often suggested.
P.S. One suggestion that's come up from time to time is to form the Senate from a national random sample of adults. This would give you all the representativeness you'd want.
P.P.S. Apparently the House has four (former) blue-collar workers: Phil Hare of Illinois, Stephen Lynch of Massachusetts, Mike Michaud of Maine, and Bob Brady of Pennsylvania. I don't know how many former nurses, police officers, or child care workers they have.