Recently, we’ve seen two polls with decades of data post record low favorability ratings for the Republican Party: Pew and CBS/NYT. Of course, we know better than to pay attention to any one or two polls, so above you can see a local regression line through all the data (excluding weekly polls, which swamp the signal). You can view and play around with the most recent data yourself at HuffPost Pollster.
What is immediately obvious is that the net favorability for Republicans (red line) has indeed plummeted to its lowest ever level during the primary season. For Democrats (blue line), on the other hand, favorability has increased to essentially a net neutral rating.
Even more stunning is the realization that Republicans have had a negative net favorability for more than a decade—ever since Hurricane Katrina, when it became painfully obvious that incompetent Republican governance does not actually keep us safe.
Arguably, Republicans failing to run their part of the government also caused Democratic favorability levels to plummet, and stay relatively low, since the inauguration of President Obama. As a strategy, Republicans’ obstruction seems to have been successful at lowering opinions of Democrats.
How does this relate to the 2016 election? Find out below.
When we look at the difference between Democratic and Republican net favorability, there’s a pretty clear pattern. A very strong Democratic advantage (2008) translated into the best vote share for a Democrat in decades.
It’s tempting to plot out a measure of electoral success (Democratic vote share or margin) versus the Democratic Net Favorability Advantage. But with only five non-Perot elections to work with, it’s probably not the best idea. However, there’s a strong correlation for those five data points, and we can say without hesitation that the current state is good for Democrats.
The favorability ratings, however, can change rapidly during election season. Both parties have consolidated support from their own members in the prelude to the 2008 and 2012 elections, as can be seen in the first graph up top. With Donald Trump as their nominee, it’s possible that doesn’t happen as much this year for the GOP—but it wouldn’t be surprising.