Every election comes with its own 'branded' swing voter. In the 1990s and early 2000s, we had soccer moms and NASCAR dads, as well as security moms and office-park dads. Over the last four years, the typical swing voter was either defined as an upscale suburban resident (Peloton moms) or a white working-class voter in small-town America. But, these groups all share one thing in common: race. The working assumption in modern politics is that the more diverse the electorate, the better for Democrats, and the whiter the electorate, the better for Republicans. 

And, as a broad generalization, this is true. However, it doesn't do justice to the inherent swingy-ness found within non-white communities. 

Additionally, there's a belief that swing voters are those who literally swing between voting for one party one year and the other party the next. While those voters do exist, they tend to overshadow the larger cause for swings in partisan support from election to election: the churn of new or low-propensity voters into the electorate. 

In his recent analysis of the 2020 election by population density, Boston College's David Hopkins credits Biden's narrow Electoral College victory to a small, but substantial improvement over Hillary Clinton's 2016 showing in the smaller metro areas like Harrisburg, Pennsylvania, Omaha, Nebraska, and Lansing, Michigan. 

Hopkins argues that a "pro-Trump national shift among non-white voters, especially Hispanics" meant that Biden didn't run up his margins as significantly as expected in racially diverse top 20 metros like Chicago, Los Angeles, Orlando or Cleveland. 

"The biggest aggregate movement toward the Democrats in 2020 occurred within metro areas outside the Top 20. These other 251 metro areas cast somewhat fewer collective votes (41% of the total two-party vote in 2020, compared to 45% for the top 20 metros)," writes Hopkins. "But their lower levels of racial diversity meant that the ongoing pro-Democratic trend among college-educated whites was less likely to be numerically counteracted by racial minorities' movement towards Trump." 

In other words, it was the lack of racial diversity (as well as significant presence of white, college educated voters) that helped Biden improve over Clinton's 2016 showing in these smaller metro areas. 

In their Post Mortem' of the 2020 election, Equis Research, a progressive organization focused on Latino voters, concluded that "a segment of Latino voters demonstrated that they are more 'swing' than commonly assumed."

In fact, writes Equis, "Trump appeared to make gains in the last year of his term among voters usually on the sidelines of politics. While Latinos are often treated as a target for registration and turnout, it was less-frequent Hispanic voters who showed the most 'swing.'" 

In other words, the assumption that less actively engaged Latinos are more liberal or at least more open to voting Democratic was turned on its head this election. 

To me, one of the more interesting slides in the Equis analysis was one showing how Democrats had modeled the vote intention of Latino early/absentee voters in the Rio Grande Valley pre-election. On a scale of 0-100 (with 100 being very Democratic and 0 being very Republican), they had predicted that 37 percent of voters who were the most Democratic-leaning (a score of 80 or higher), were either first time or infrequent voters. Among the most pro-Trump group (those with a 40 or below) score, the infrequent/new voters were a much smaller percentage of the vote at 16 percent. In other words, if you saw just these two data points, you could reasonably argue that an increase in turnout by low-propensity Latino voters would help Democrats.

But, those Latino voters with a score between 40 and 80 (i.e., not strongly Democratic or Republican) were actually the most likely to be a new or infrequent voter. Just 15 percent of these 'persuadable' voters had voted in three of the last three elections (compared to 54 percent of the most GOP leaning and 33 percent of the most Democratic-leaning). Meanwhile, a whopping 57 percent had either never voted or had voted in only one of the last three elections. Which is why, as Carlos Odio, a co-founder and Senior VP at Equis, told me, it's not enough for Democrats to simply register more Latinos and "bank on passive support" from them. While Democrats continue to win a majority of Latino support, the fact that races in battleground states are decided by the narrowest of margins means that Democrats can't afford many defections. Think of the Democratic support from Latino voters like someone carrying a big armful of oranges, said Odio. Democrats can't afford to let any drop, while Republicans don't need their own armful but simply "need to flick some out" of Democrats hands. 

Biden's ability to break through with a message that will resonate with these voters is going to be critical for the Democrats' political success in 2022 and 2024, says Odio. Trump's reality show name ID and larger than life persona transcended the typical 'political' lane. Biden can never compete with Trump at that level. Even so, says Odio, he needs to find a way to show these voters how he's delivered for their community, especially on issues like the economy. 

But, it's not just low-propensity Latino voters who upended conventional wisdom in 2020. An analysis released this week by a consortium of five Democratic pollsters, found that their polling underestimated the share of low propensity white, rural and non-college voters. "Among low propensity voters—people who we expect to vote rarely—the Republican share of the electorate exceeded expectations at four times the rate of the Democratic share," write representatives of these firms. "This turnout error meant, at least in some places, we again underestimated relative turnout among rural and white non-college voters, who are overrepresented among low propensity Republicans." 

Even after making adjustments on weighting post-2016, these Democrats admit they were still unable to capture the true extent of the pro-Trump electorate. "There is something systematically different about the people we reached, and the people we did not."

Pew Research found similar challenges to getting Trump-friendly voters to participate in their online panels. Overall, they concluded "that achieving proper representation of Republicans is more difficult than it used to be. Survey participation has long been linked to individuals' levels of education and social trust. Now that the GOP is doing better attracting voters with lower levels of education and, according to some analysts, doing better than in the past attracting low trust adults, Republican participation in surveys is waning, increasing reliance on weighting as a corrective."

None of these organizations offered a silver bullet to better identify and/or categorize the political leanings of infrequent voters. Pew and the Democratic pollsters say they will be tweaking their methodology and experimenting with different ways to try and reach hard to find voters. But, perhaps one of the best short-term solutions is to not assume that an infrequent or new voter can easily fit into one political camp or the other.

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