We’ve all heard about October surprises, which in this unpredictable election year have melded into a November surprise, too, courtesy of FBI director James Comey’s running commentary on the Hillary Clinton e-mail investigation.

But there is another wild card this Election Day that has nothing to do with a talkative FBI director. It comes from the United Kingdom and its experience with the Brexit vote this spring to leave the European Union.

Few recognized the depth of the Brexit dissatisfaction and missed the trend. Pundits and conventional GOP supporters made the same mistakes during the spring primaries.

Now I think that there are pockets of Trump support in the general election that have been underestimated. I don’t think it is enough to turn the election away from Clinton, but it would be foolish to believe that Trump’s line of thought and support would disappear after the election.

I think four Brexit themes support the idea that there is a silent Trump vote that people may be overlooking. A deep dissatisfaction with a broken immigration system. Lost faith in public institutions. A need for simple solutions to complex problems. A desire to send a message that overrides a full appreciation of the consequences.

Many pundits say Trump has a very, very narrow path to victory based on the nation’s changing demography and electoral computations. I think they are right. But that a narrow path even exists at this point in the race suggests to me that some voters are looking for a reason to vote for Trump.

I’m more comfortable with Clinton in the White House. Still, I can see Trump’s appeal to voters who see the world in transactional, us-vs-them terms and feel mired on the losing side of the transactions. He has touched on something that is real in American political discourse and isn’t going away quickly.

His divisive tone has made it harder to divorce the message from the messenger, which is why some who have empathy with the message are having such a tough time reconciling the conduct of the messenger.

In the spring, I wrote that Brexit was an inevitable consequence of global change. That is what we are seeing playing out here - disapproval of the direction the nation is headed and the willingness to fire a political nuke or two into the machinery regardless of the consequences.

This is a lesson from Brexit, and could be the legacy of the Trump campaign that also was underestimated from day one.

Jim Mitchell is a columnist for the Dallas Morning News.