I don't believe that there is a racist majority in America; nor is there a large racist plurality. Whether it is the folks who are left behind by the new economy or those with unaffordable healthcare, a lot of people weren't helped by the government policies in the past couple of decades and chose to blame the party who has been in power for the past decade. The Clinton campaign just couldn't offer anything for them. They mostly focused on why one shouldn't vote for the Donald. Trump focused on why they should vote for him with promises to change things: empty as those promises may end up being, he was the only one peddling hope and change.
If you can't open your eyes to how these people are affected by government policies (some can be squarely blamed on you, some maybe not), you will not learn how to earn their votes back. You can keep blaming the Comey or a 3rd Party. Or yo u can recognize that this was an outright rejection of the establishment: both of the Democrats and Republicans; at least the Republicans have less to worry about with the control of White House for four years and both houses of the Congress for at least two. If you're looking at these voters with the racist narrative, the only option you have is to fight them; recognizing that these are non-deplorable good folks some of who voted for Obama in the past but are now lost is the first step of figuring out how to bring them back. Also look at the democrats who stayed home and figure out how you failed to inspire them. Now, was the Klan all for Trump, sure, but they are not as influential as the millions of good men and women who supported the Trump movement.
What didn't help Hillary is that she was running one of the most opaque campaigns in recent memory - save for Trump campaign, which didn't matter for him - refusal to do press conferences, no traveling press escort or anything that deviated from the scripted message that the campaign wanted to present. The media didn't make a big deal about it, but it denied the voters to get a close look at her. In this age that demands 24/7 accessibility, transparency and authenticity, she fell flat; she wasn't trusted because many folks didn't know much about different aspects of her. Trump may have refused to divulge a lot of things - tax returns or health records - but being a loose cannon to the point of alienating a lot of people, he maintained the aura of authenticity.
Now, the Trump administration will take charge in earnest in a couple of months - notwithstanding the crazy-pot theories spread by left on how he can be stopped, much like the ones the right used to trade in during the Obama years - and no one can really predict how it is going to go down. Trump doesn't have a proclivity to follow any defined ideology or pattern. For one thing, he is definitely not going to spread theocracy as some in the right would hope. Even the policies on immigration that he is saying he would do is far less severe than what other countries like Australia currently practice. Even with Republican control of both houses of the Congress, there are enough checks and balances left to control what he could do - Democrats still have the tool of filibuster after all.
This is probably a blessing in disguise for the democratic party. After all, the best growth in its popularity came during the eight years of George W Bush presidency that culminated in it claiming a full filibuster proof control of Congress and previously unthinkable election of the first black president. As they used "Blame Dubya First" as a strategy to widespread success, "Blame Trump First" would probably prove to be equally successful. As in sports leagues, rebuilding years usually lead you to great success eventually. Unless you are Philadelphia 76ers or Cleveland Browns.