Following success in the Nevada state primaries, Republican presidential candidate Donald Trump looks set to extend his lead in the race for the Republican party nomination.
According to NBC polls, Trump leads in four of six states going into Super Tuesday next week.
Mike Thompson, Managing Director and Chairman at Standard & Poor's Investment Advisory Services, said he didn't think investors knew how to respond to Trump's run.
"I think markets are in a kind of a state of disbelief. I don't think they've ever seen anything like this.
"The extreme between the two parties is really striking," he told CNBC Wednesday.
Thompson said the election process itself was like something that nobody has ever dealt with.
"It's like somebody broke all the rules.
"Its unfamiliar territory and it's hard to take a historical precedent and apply it in this situation," he said.
Tax reform has so far been largely absent as a debate topic in the U.S. election race.
U.S. corporations pay 40 percent tax on domestic operations, one of the highest rates in the world according to KPMG.
Thompson claimed levies on U.S. companies were a poor way of collecting revenue and raised less than 20 percent of U.S. government taxes.
"Some people are making the argument that you can create more jobs and income tax from personal income tax receipts by just getting rid of the corporate tax rate" he told CNBC.
"At the same time you vault the U.S. to the premier place, in the biggest unified consumption engine, to be a business owner."