Dem
51
GOP
49
Divided government is nothing new for the U.S. In theory, the system of checks and balances makes that possible—in contrast with parliamentary systems, in which the party or coalition of parties that controls the lower chamber of the parliament gets to name the prime minister and run the show with largely unchecked power until the next election. With the three elected parts of the U.S. government being the presidency, Senate, and House, there are six ways to have divided government: DDR (Democratic president and Senate, Republican House), DRD, DRR, RDR, RRD, and RDD. Right now, we have the first combination, DDR. However, in January 2025 we could have DRD. This is very rare, since we have to go back to the 50th Congress (1887-1889) for the last time a Democratic president and House had to contend with a Republican Senate.
To achieve this situation, a plausible, but very rare, event will have to take place: both chambers of Congress flip, but in opposite directions. In the Senate, the Democrats face a brutal map and need to hang on in two very red states, Ohio and Montana, as well as in some other tough states. In the House, there are many factors pointing to the slim Republican majority giving way to a more substantial Democratic majority. And of course, to get DRD, Joe Biden will have to win a tough race, but historically, incumbent presidents have won about two-thirds of their races, so a Biden win would hardly be unprecedented.
An analysis of national demographics sheds light on why a Republican Senate should be normal. The median state population is 4.58 million, halfway between Kentucky (4.51 million) and Louisiana (4.66 million). The people who live in the 25 less-populous states, from Kentucky on down to Wyoming, tend to be much more rural, non-college-educated, white, and Republican than the national average. Their 50 senators should "naturally" be Republicans. With Louisiana being the next state above Kentucky on the list, no wonder Democrats can't achieve big majorities in the Senate.
Race is a big factor here. Among the 25 least-populous states, only five (Alaska, Hawaii, Mississippi, Nevada, and New Mexico) are more racially diverse than the nation as a whole. When you look at lack of a college degree and which states are the most rural, the 25 least-populous states score again. There are 23 states left where non-college whites are still in the majority, and 15 of those 23 are among the 25 least populous states.
Demographics are much of the story, but not all of it. Geography also plays a role. While the South is solidly Republican, the Southwest isn't anymore. After the 2002 election, Arizona, Colorado, Nevada, and New Mexico provided Republicans with 6 senators. Now all eight seats are occupied by Democrats.
All this said, there are 18 Democratic senators from the 25 least-populous states (Connecticut, Delaware, Hawaii, Maine, New Hampshire, New Mexico, Rhode Island, Oregon, Montana, and Vermont). Still, the skewed demographics do give the Republicans a good start, which is added to by some of the big red states, like Texas, Florida, and Ohio. All in all, the possibilities for the Democrats to have anything but the barest majority in the Senate any time soon are low. They already have the four Senate seats from the most recent swing states, Arizona and Georgia. The only possible other swing state where the Democrats could eventually capture both Senate seats is North Carolina. Other than that, the pickins are slim. (V)