From the table on Wikipedia, the record by percentage of EC votes is 24% (72/303) in 1860. By a former VP, not a Jill Stein.
Splitting the vote in PA that year made Lincoln’s win a certainty. Nice that a spoiler candidate worked against the pro-slavery regressives of the era.
Their party split when the national convention didn’t agree they’d abide by the SCOTUS ruling on States’ Rights, LOL, absolute shitheads. And then they also did an insurrection.