Does Obama Have White Voter “Problem”? — The Monkey Cage: "Since the mid-1970’s Democrats have had a white voter “problem.” Obama is a Democrat. This is by far the best lens through which to view white support for Obama. Conversely, it is also the best lens through which to view black support for Obama. For example, LBJ received essentially the same level of black support in 1964 as did Obama in 2008. ... In 2008, Obama garnered about 43% of the white vote. This was the high water mark for Democratic presidential candidates since Jimmy Carter in 1976 – not coincidentally about the time in which party polarization starts to take hold in the U.S. Put differently, Obama received as much or more white voter support than Kerry, Gore, Dukakis, Mondale, Carter (1980), and even Bill Clinton (see the data here or see the historical chart in the Post piece here)."
The entire post is short and very much worth your time. I just wanted to stress the above because I keep seeing identitarians obsessing over the white vote. If racism is the reason for the vote, white racism hurt Clinton more than Obama.