“The share of third-party/independent presidential voters plummeted by nearly four percentage points since 2016, from 5.7 to 1.8, while Joe Biden exceeded Hillary Clinton’s haul nationally by 2.6 percentage points and climbing steadily, as the populous blue states continue to pad his lead.
So while Michigan, for example, was delivering essentially the same results for Trump as four years ago, the Great Lakes State was subtracting 3.6 percentage points from third-party candidates, and adding 3.2 to Biden”
…
“Arizona has a similar story: down a combined 4.6 for the marginal names, up 4.3 for the Democrat; 92 percent E.V. All over the country, the president was able to bring out more of his voters, but with only a handful of exceptions was unable to expand on his core share of support by persuading fence-sitters to choose the Republican side.”
…
“There were 7.8 million third-party voters last time, and just 2.7 million this time, so any strong lean by the remaining 5 million-plus was always going to dwarf whatever impact partisans may attribute to “spoilers.””