I think this article in The NY Times is excellent...very thorough and very interesting. https://www.nytimes.com/2023/09/11/upshot/electoral-college-trump-2024.html

As they say the devil is in the details - and in the US the national polls mean nothing. It's a state by state analysis that counts and right now there are about five or six states which will decide the next election. It's always been that way and it's sad for the rest of us whose vote for President barely counts.