But the most important factor was surely Trump. Obama polarized public opinion by racial attitudes primarily because of who he was, not because of what he said or did. Daniel Gillion’s new book shows that Obama spoke about race less than recent Democratic presidents and was criticized by black leaders and intellectuals for refusing to push for race-specific policies.

In stark contrast, Donald Trump repeatedly went where prior Republican presidential candidates were unwilling to go: making explicit appeals to racial resentment, religious intolerance, and white identity. So much so, in fact, that more than half of Americans consistently said that the term “racist” described Donald Trump in YouGov/Economist surveys conducted during the fall campaign.

Donald Trump’s racially divisive campaign inevitably made racial attitudes more important in the general election than if he had not been the Republican nominee. I showed earlier that racial attitudes were stronger predictors of whites’ preferences for Trump or Clinton than they were in hypothetical matchups between Clinton and Ted Cruz or Marco Rubio.

Much like Obama before him, Trump simply seems to make racial attitudes matter more in public opinion. That “Trump effect,” combined with eight years of racialized politics under President Obama, means that racial attitudes are now more closely aligned with white Americans’ partisan preferences than they have been at any time in the history of polling.