I noted here that Romney garnered a lower proportion of all votes cast in the 2012 Iowa caucus than he did in 2008 (though only 0.5% fewer votes in absolute number). Alex Seitz-Wald made a parallel observation regarding the Missouri, Colorado and Minnesota contests. In each of these states Romney attracted a dramatically lower absolute number of voters in 2012 than in 2008.
But looking at just one repeat candidate’s performance in consecutive elections can be misleading. The number of votes a candidate attracts in one primary election cycle versus the next could change because one year had unusually good or unusually bad weather or because a state moved its primary to a more versus less exciting spot on the calendar. Further, the same absolute number of votes has a different meaning each election cycle depending on how many other candidates are still in the race and on whether it is a high turnout or low turnout year in general.
There is however a way to roughly control for all these factors in assessing Romney’s performance in 2012 relative to 2008, because Ron Paul is also a repeat candidate. Whatever generic external positive and negative factors have affected Romney’s primary vote totals will also have affected Paul’s: The sun shines — or fails to — on all candidates’ voters equally.
The chart below presents the percent change in number of votes received by Paul and Romney in each of the nine states that have so far voted. The comparison with Paul make Romney’s 2012 run look even less impressive than it does already. Paul’s growth in number of votes from 2008 to 2012 beats Romney’s in all states, and in no case did he decrease his number of votes (his smallest gain was 1.5% in Nevada). In states where a generic factor helped all the candidates net a higher absolute number of votes, for example South Carolina’s 35% higher turnout in 2012 than in 2008, the bump Romney got in relative performance still lagged Paul’s. And Romney’s post-Florida run of decreasing his absolute number of voters from 2008 to 2012 — which he extended today in Maine — can’t be blamed on generic external factors: Ron Paul increased his vote totals in all five of those states.
Note: Maine results imputed at 7pm EST based on 95% of returns. Romney’s Iowa change does not show on the chart because his number of votes in Iowa in 2012 was almost equal to his 2008 total