If Mr. Trump wins, two companies that seem poised for an immediate pummeling are AT&T and Time Warner, given how much Candidate Trump has objected to their recently announced merger plan. AT&T, by the way, also happens to have a huge business in Mexico.

The biggest test for the stock markets might be pegged to the future leadership of the Federal Reserve. “There is much more uncertainty regarding who Trump might nominate, though he has made it clear he would not renominate Chair Yellen,” Goldman Sachs wrote in a note to clients. “His criticisms of Fed policy are somewhat ambiguous; he has suggested rates have been left too low for too long, but also warns of negative consequences of rate hikes. We would expect that financial markets would view a Trump victory as having slightly hawkish implications, since it would make a change in what many view as a dovish-leaning Fed leadership much more likely.”

A handful of economists have suggested that despite all of the promises made by the candidates, the outcome of the election might not actually decide what direction the markets will take.

“Putting aside their personalities and policy proposals, it will likely not matter who the next president is when it comes to where markets go,” Mr. Boockvar wrote in a note to clients. “As we are in the second-longest bull market of all time, and as we approach the eighth year of this economic expansion,” he wrote, “odds are high that whoever the next president is, they will preside over a recession, a bear market and rising debts and deficits.”

That might be too bearish of a view, but given that we’ve had a financial crisis of some sort about every eight years or so for the last several decades, it is hard to believe that we will go through the next four years without a hiccup. If merger activity is a gauge of the market’s cycle, the recent spate of deals suggests we’re closer to the ninth inning than the first.

Lawrence G. McDonald of ACG Analytics, who has commented on the potential benefits of a Trump presidency, said, “Trump will create a colossal panic, but the relief rally will be outstanding.”

Mr. McDonald, who publishes a newsletter on global political risk called the Bear Traps Report, said he believed that “Trump’s bark found in his anti-globalization position in reality will be a lot worse than its bite in terms of actual implementation.”