By Cornell W. Clayton, Thomas S. Foley Distinguished Professor of Government anddirector of the Thomas S. Foley Institute for Public Policy and Public Service at Washington State University
The presidential campaign begins in earnest this week as 20 Democrats debate each other in Miami over who should take on President Donald Trump in next year’s election.
Is it possible to predict the 2020 election before a single primary vote is even cast?
Disregarding Yogi Berra’s sage advice to “never make predictions, especially about the future,” here’s how a political scientist would do it.
First, I would explain that contrary to popular belief the polls in 2016 were pretty accurate. Nine of the ten major tracking polls predicted Clinton would win the popular vote, which she did by 3 million votes. Eight predicted her vote share within their margins of error.
The polls also accurately predicted the Electoral College in all but one state, Wisconsin. In six states, polls were too close to call, so they were “toss-ups.” Five of these ended up voting Trump. But the election turned on just three states — Wisconsin, Michigan and Pennsylvania — where the combined margin for Trump was about 86,000 votes, less than half of 1%.
The lesson from 2016 isn’t to doubt the polls. It’s when polls tell you it’s too close to call, you should believe them!