Even those who have long embraced the Democratic dream of a “blue Texas,” powered by mobilizing the state’s growing Latino population, probably never imagined such staggering Democratic gains in once-solidly Republican areas. Yet the poll suggests that Hispanic voters might just be the group that keeps the state red a while longer.

Mr. Biden has a lead of only 57 percent to 34 percent among that group, somewhat beneath most estimates of Mrs. Clinton’s support among Hispanic voters four years ago. The finding broadly tracks with national surveys, which have shown Mr. Trump improving among Hispanic voters compared with his 2016 standing. Similarly, Hispanic voters in the Times/Siena poll say they backed Mrs. Clinton by a margin of 60 percent to 29 percent…

Mr. Trump also shows modest but meaningful strength among Black voters, who back Mr. Biden by a margin of 78 percent to 12 percent. Black respondents in the survey said they voted for Mrs. Clinton over Mr. Trump by a somewhat larger margin, 82-8, in 2016.