The coronavirus pandemic has raised a host of new questions about the 2020 election. What will the economy look like in November? How do voters think President Trump is handling the crisis? How will Americans physically cast their votes? And could the current moment be so extraordinary that it outweighs partisanship and causes Republican voters to abandon Trump in November?

For the last question, at least, we can look to history for some clues. The 2008 election isn’t exactly parallel to our current situation, but there were some similarities. Back then, an unpopular Republican president, George W. Bush, sat in the White House amid an economic disaster, though he wasn’t running for reelection. But the environment that GOP nominee Sen. John McCain was running in may be not unlike the one Trump faces in 2020. (One important caveat: When McCain ran, the GOP had already held the presidency for two terms, and historically, it’s rare for the same party to win three times in a row. Conversely, it’s very common for incumbent presidents like Trump to win a second term.)

The 2008 election resulted in a Democratic landslide, as then-Sen. Barack Obama defeated McCain by about 7 percentage points in the national popular vote. Considering how polarized our politics are, this was a large victory by modern standards, as the chart below shows.

Democrats didn’t just take the White House either. They also made huge gains in the Senate and House of Representatives, adding to their majorities in both chambers.

But Democrats didn’t win because Republicans were fleeing the party or voting for the Democrat en masse — McCain still won support from most Republicans who turned out that year. The 2008 Cooperative Congressional Election Study, a massive survey that asks Americans about their politics and voting habits, found that McCain won 95 percent of self-identified Republicans who voted, as well as 90 percent of independents who leaned Republican. Similarly, Obama won the overwhelming majority of Democrats and Democratic-leaning independents (92 and 93 percent). This partisan split is in line with results from other recent presidential elections, too.

The difference in 2008 was the makeup of the electorate: 51 percent of voters identified as Democrats or Democratic-leaning independents while 41 percent identified as Republicans or Republican-leaning, according to CCES data.

Some of this was because Democratic identification more or less peaked in 2008 while Republican identification was at a low point. Democrats also saw strong turnout from Democratic-leaning demographic groups like African Americans, who showed up in historic numbers to vote for America’s first black president. And getting those partisans to the ballot box was vital to Obama’s victory, as he actually lost among “pure” independents, or those who didn’t lean toward either party, by 11 percentage points. Fortunately, for Obama, true independents only made up about 7 percent of the total electorate.

Of course, we don’t know how many votes McCain might have lost because people abandoned the GOP before the election or because some Republicans simply didn’t show up to vote. Corwin Smidt, a political scientist at Michigan State University, told me that it’s likely that some people switched parties because of the financial crisis or the Iraq War, but he said it was probably a fairly small share of the electorate. One study estimated that Obama may have won 15 percent of voters who said they backed George W. Bush in 2004.

Smidt told me he thought we could see some people switch parties here in 2020, though, with some Republicans leaving the party because of the economic downturn caused by the coronavirus. In fact, there is some evidence that a small share of voters have already shifted parties during the Trump presidency. In 2017, the Pew Research Center found that roughly one-tenth of Democrats and Republicans (including those who leaned toward one party) defected to the other party over the course of the 2016 campaign and in the early days of Trump’s presidency. But Smidt cautioned that we’re still likely only talking about a small slice of the electorate who might switch parties in 2020 because Trump is so polarizing and there is such a gulf between Democrats and Republicans on most political issues. “If party differences are clear, people are less likely to switch,” said Smidt. And right now, he says, “It is hard for people to switch.”

Studies have shown that partisans are more likely to stick with their party now than they were just a few years ago, and people feel more negatively than ever toward members of the other party. Surveys also suggest that the overall share of people who identify with or lean toward each party has been relatively stable. So that means Trump’s intraparty support may be just as strong as McCain’s was in 2008. His approval rating has been remarkably steady, and he’s enjoyed very strong Republican backing throughout his presidency, with as many as 91 percent of Republicans and 89 percent of Republican leaners approving of his job performance before the 2018 midterm elections, according to CCES data for registered voters.

There’s little sign that Republicans are backing away from Trump either. A late March poll from Pew found that, among registered voters, 92 percent of Republicans approved of Trump, as did 79 percent of independents who leaned Republican. While the approval among leaners may seem low compared to the 2018 CCES data, it was actually similar to previous Pew polls that found 70 to 75 percent of Republican leaners approved of Trump.

So just like McCain in 2008, Trump likely still has very strong backing from Republicans that will almost certainly hold up even if things go poorly for him in the coming months. What we can’t know, of course, is just how much a bad economy might move people away from the GOP before the election, or how many partisans might simply stay home.





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