New York (CNN Business) A version of this story first appeared in CNN Business' Before the Bell newsletter. Not a subscriber? You can sign up right here.

S&P 500 SPX President Donald Trump faces removal from office, yet markets have shrugged off impeachment and continued to march higher over the past several months. Theis up nearly 11% since House Speaker Nancy Pelosi announced a formal impeachment inquiry on September 24.

Much of that is almost certainly because Trump's acquittal has been telegraphed since the beginning of the impeachment inquiry. More than a dozen Republican senators would have to defect to have any chance at removing Trump from office, an outcome that has the slimmest of chances of taking place.

Even if Trump were impeached, he would be replaced by a member of the same party: Vice President Mike Pence. Still, markets hate uncertainty. Although Trump is the odds-on favorite to win reelection in November, investors could be concerned about Pence's chances against a Democratic field that includes progressive candidates like Elizabeth Warren and Bernie Sanders.

"If the trial in the Senate unveils any material information that threatens policy continuity, financial markets may react negatively to the added uncertainty," said Jameel Ahmad, global head of market research at Forextime, in a note to investors.

Read More