Ronald Brownstein in The Atlantic has a piece on undecided voters, The Undecided Voters Are Not Who You Think They Are, that has some interesting tidbits (although if you are paying attention, the undecided voters may, indeed, be who you think they are).

Campaigns typically describe the first group of reliable but conflicted voters as persuadable; they frequently describe the second group as irregular voters. Persuadable voters get the most attention from the media, but campaigns recognize that irregular voters can loom much larger in the outcome—especially in presidential elections when more of them ultimately participate.

“There are a gajillion more of those [irregular] people than the Harris/Trump ‘I don’t know; I’m still thinking about it’” kind of voter, Anat Shenker-Osorio, a communications consultant for Democrats and progressive groups, told me. “There are more humans who are non-habitual voters than there are voters who swing back and forth. That’s just math.”

The piece notes something I have emphasized for years: while a lot of people will say they are persuadable, the reality is very few people (especially likely voters) are really on the fence between the two candidates.

“There is an immaterial number of ‘certain to vote’ people who are undecided,” says the longtime GOP pollster Bill McInturff, whose firm has conducted the NBC poll along with a Democratic partner for decades. This is a view widely shared among strategists in both parties.

I would say it is more than a widely shared view; it is an empirical reality.

Along the same lines, Mike Podhorzer (a one-time AFL-CIO political director) noted:

 “Almost all” of the people who said they were undecided at any given time turned out “to actually be on one side or the other. It was just how they were asked.”

The number is estimated as follows:

Among the operatives and strategists that I spoke with in both parties, the best estimate is that just 4 to 7 percent of voters in the battleground states are such persuadables—people highly likely to vote but genuinely uncertain about whom they will support.

That comports with a Pew study I wrote about back in 2019.

Who do they appear to be in this cycle?

These persuadable voters wavering between the two candidates split mostly into two camps. The largest group may be the traditionally Republican-leaning voters (including many who identify as independents) uneasy about Trump. These voters are the remnants of the suburban, largely college-educated constituency that favored Nikki Haley during the GOP primaries.

[…]

The other big group of potentially persuadable voters, according to the NBC, Pew, and New York Times/Siena polls, are younger and minority voters who dislike Trump but are disappointed by their economic experience under Biden—and are uncertain whether Harris offers a sufficient change in approach. In the recent Pew survey, Hispanics who currently support Trump were much more likely than white voters to indicate that they might change their mind; for Harris-leaners, both Hispanic and Black voters were more likely to say they might reconsider. For both candidates, more younger than older voters indicated that they might switch.

As the piece notes,

In the end, however, neither party expects too many of the voters who are telling pollsters today that they might switch to the other candidate to actually do so. The bigger prize for the two campaigns is the irregular voters who are, as Longwell put it, deciding “whether they are going to get off the couch” to vote at all.

The piece provides some descriptions of who these irregular voters might be, but in a way that defies easy categories and excerpting, so I suggest clicking through to peruse.

The piece concludes thusly:

The thin sliver of reliable but persuadable voters still undecided between Harris and Trump matter in the crucial states, Podhorzer said, “because everything matters” there. But he predicted that whichever party turns out more of the irregular voters in its favor will win those states. That’s the bitter irony of modern U.S. politics: In a country divided so ardently and irrevocably between the two parties, the people who aren’t sure they care enough to participate at all are the ones who could tip the balance.

In some ways, this just saying that in the really close states, everything at the margins matters (including things like the weather). Without any doubt, the GOTV efforts are going to matter and there are reasons to believe that the Harris campaign and its allies are better prepared and funded for that than is Team Trump (which is more focused on the grift).

In regards to Brownstein’s conclusion, I would go a step further: it is a bitter reality that such voters could decide the election because of where they live, giving their votes more power and salience than voters in other parts of the country.

Still, I will have to note that any truly close election is, in some ways at least, settled by voters who have softer opinions on the candidates or who simply don’t understand or really care about the outcomes (at least as compared to most voters, especially the ardent partisans).