The United States is a giant country, in both population and area.
Currently, our country is divided into 435 single-member Congressional districts with an average population of just over 750,000.
A 695-member unicameral Congress elected by ranked choice voting across 164 multimember districts could look like this:
The transition from the current two-party system to a true multiparty system would not happen overnight. If, overnight, we started electing Congress with Proportional Ranked Choice Voting, I believe that while two parties would remain dominant at first, each party would face immediate competition from its flank. So deep is our collective dissatisfaction with the two parties that if there were an electoral system that made alternative parties viable, I believe 40 percent of the people who vote for Democrats would consider voting for a left-wing alternative (I am part of that 40%), and that 40 percent of the people who vote for Republicans would consider voting for a right-wing alternative. Also, while many voters may prefer instead an alternative centrist party, I do not model that here.
With a Proportional Ranked Choice Voting system, we could immediately have a four-party system. Competition would be between Republicans and Democrats (purple), Democrats and Progressives (teal), and Republicans and Libertarians (orange). The data I used to estimate the outcome for each district is based on an aggregate of statewide elections from 2016 – 2020. Politics changes quickly, so the data is already out of date, but it’s close enough to current to provide an estimate for how we might begin to break the two-party system. My analytic methodology is explained in detail in part B of this chapter.
Likely, no party would win the 348 seats required for an outright majority. Consider, a Democratic Party focused on moving to the right to persuade conservative voters could lose as many seats to a Progressive Party from the left as it might gain from a Republican Party to the right. A new party from the left could win up to 115 seats, and a new party from the right could win up to 108 seats (assuming a roughly 60 – 40 split in favor of the established party among voters who voted that party, and that each established party had only one splinter party). Alternative parties would be competitive in 45 states; all 8 states lacking alternative party competition are small, single district states (Maine, Rhode Island, Montana, Delaware, Alaska, Vermont, Wyoming, Four Territories). Only one state, Alaska, would see fewer people living in competitive districts. In Alaska, both Democrats and Republicans would win one seat, and Alaska’s idiosyncratic politics could result in unforeseen competitiveness.
I define a competitive district as a district in which the electoral outcome of at least one seat is uncertain. About 10 percent of Americans, 34 million people, live in a competitive congressional district for the 2024 elections, according to the Cook Political Report as of 9/7/2023. According to my model, with these new maps more than 75 percent of Americans, 281 million people, would live in a competitive district, and 43 of the 53 states would feature competitive districts. Alternative parties could compete for 223 seats, about 30 percent of Congress.
To make these projections, I drew new multimember districts for every state and analyzed the partisan makeup of each state to estimate the electoral outcome. These maps are the opposite of gerrymandered. I actively worked to counter my implicit urban and liberal biases and tried to draw districts to favor more rural and conservative populations. I discuss this in detail in part A of this chapter.
These maps and this analysis show what elections might look like immediately following the implementation of P-RCV. After several election cycles, there would likely be more parties as the existing Democratic and Republican coalitions fractured, as described in Chapter 6.d.
Because no party would be likely to win a majority, to be elected Speaker of the House a legislator would almost certainly be required to form a coalition government, as in other multiparty democracies. Congress would be forever changed.