Several big names have been arguing that Sanders has done well in caucuses, but not primaries. This includes Kos recent front page post and some over at 538.
Bernie Sanders Continues To Dominate Caucuses, But He’s About To Run Out Of Them
All five of Sanders’s wins this week came in caucuses. The problem for the Sanders campaign is that there are only two caucuses left on the Democratic primary calendar.
I would like to say that I very much respect and appreciate their work, but I think they are missing the forest through the trees on this one. Their argument looks persuasive at first glance, but I have argued that it is just as easily, if not more so, explained by regional differences. However, I think this argument has been largely ignored. So, I have used simple statistical analysis and graphs to give people visual and numeric support showing that my argument is better supported by the data.
The regional argument
States outside the South/Southwest are strongly statistically different from the rest of the states so far. In other words, the simple statistical analysis shows that Sanders is winning more delegates in states outside the south/southwest. This strongly supports a regional argument.
The obvious issue here is that all southern states were primaries while many of the northern states were caucuses. So let’s take a look at these while isolating variables in two ways.
- Isolate a region and compare caucuses and primaries
- Isolate primaries only and see if there is a difference between regions
Isolate a region and compare caucuses and primaries
In this example, the caucuses and primaries are not statistically different when looking at states outside the south/southwest only. However, Vermont is the clear statistical outlier among the primaries. Once this is excluded, the two groups are barely statistically different. So, even if Vermont is excluded from the group, the difference is not very strong compared to the difference seen between regions. This suggests that the regional argument is stronger than the caucus vs primary argument. Although it could pretty easily be said that Sanders will have a hard time winning by 70 or 80% of the vote in primaries going forward like he did in caucuses. However, he doesn’t need to do that in most cases as he needs to win about 57% of delegates going forward and all states but New Mexico (maybe Maryland) are outside of the South/Southwest.
Isolate primaries only and see if there is a difference between regions
Here we see that Sanders won delegates in states outside the south by a much greater margin than those in the south, resulting in a strong statistical difference between regions. Even when Vermont is excluded, the regions are still strongly statistically different. This again suggests that the regional argument is stronger than the caucus vs primary argument. This suggests that Sanders might be much more likely to win primaries in the remaining states since all but New Mexico (maybe Maryland) are outside the south/southwest.
Conclusion
In conclusion, the regional argument better matches the data than the caucus vs primary argument. Obviously race plays a role in different regional results, but recent states and some exit polls have shown that racial preferences change from region to region. This simple analysis is important because it shows that, while there will be less caucuses going forward, Sanders can expect to perform much better than some in the media are arguing is possible since the vast majority of the states are not in the south or southwest. While Sanders does have some of his biggest delegate wins in caucus states, he also has done well in enough primaries outside the south/southwest to suggest he can win these with significant margins or have close losses.
This also suggests that this statement is troublesome:
Sanders had a strong week, and this has been a crazy year in politics. But there’s nothing in the recent results to suggest that the overall trajectory of the Democratic race has changed. Clinton was and is a prohibitive favorite to win the nomination.
538 — Harry Enten
The problem is not that this week changed the dynamics of the race, although it certainly gives Sanders some strong momentum. It is that we have misunderstood the dynamics of the race since the beginning. Clinton’s campaign and the media have put far too much emphasis on race as the driving factor of this election. It is a factor, but so is age, sex, and region. In fact, I believe the recent results (where Sanders won in some heavily minority states and areas) show that the overwhelming difference between some of the states is their region. However, caucus vs primary also play a role.