The size of the House was last set in 1911 at 453, when the national population was 92 million. That works out to about 200,000 people per representative.
Now the US population is 326 million. Each House district now has roughly 700,000 people.
BUT Wyoming, the least populous state, has only 500,000 people in it. So, in a sense, their lone Representative has disproportionate clout in Congress.
I have long thought that the District of Columbia should be fully represented in the House of Representatives. Their sole delegate can vote in committee, but not in the full House.
I propose that DC get full representation in the House. AND that the size of each district be set by the size of the District of Columbia. At the moment, the population of DC is about 694,000 -- bigger that Wyoming.
SO If we divided 326 million by 694,000, we would expand the house to 470 Representatives.
Changing to this rule - DC always gets a Representative, and the other district sizes are based on the size of the District of Columbia - would give a reliable bright line for the slow organic development of the House.
On this basis, let's consider two other ideas about expanding Congress that have engaged political nerds and election jockeys.
2. Liberals want statehood for DC, Puerto Rico, and Guam. Six new senators, all likely Democrats, would help balance the over-representation of sparse, Republican farm states.
I think these are bad ideas, for different reasons. The District of Columbia is a city, not a state. To solve its under-representation in the Senate, I would let them vote for Senators from Maryland, from which their territory was carved in the first place.
Puerto Rico is certainly a state-sized entity. But I think it is better off as a commonwealth, with U.S. citizenship. I would not like to see English made the "official language" of the U.S., but I do think that the nearly universal use of a common language for public life is one of the great and necessary strengths of so large and diverse a country as ours. It would be bad to try to have a bilingual country, but worse to try to force Puerto Rico to switch to English.
Statehood for Guam is a non-starter, I think. The idea is only on the table as a bargaining chip, or a huge overreach.
3. Conservatives will discover that, if liberals get any traction on DC and Puerto Rican statehood, that they could split Texas into five states. This was part of the treaty when Texas was admitted to the union. Some imagine that this would mean ten Republican senators. I think it would mean that the big Democratic cities would be freed from bondage to the vast Republican countryside. The most urban of these new states would be at least purple, if not blue. Be careful what you wish for.
SO my centrist proposal for expanding Congress: a modest expansion for the House, a modest rectification of an injustice to DC residents in relation to the Senate, and no new states.