Democratic presidential candidate Sen. Bernie Sanders (I-VT) addresses supporters during his caucus night watch party on February 03, 2020 in Des Moines, Iowa. Iowa is the first contest in the 2020 presidential nominating process with the candidates then moving on to New Hampshire.

Even the possibility of Sen. Bernie Sanders winning the Democratic nomination for the 2020 elections is an important risk for markets this year, a chief investment officer told CNBC this week.

Sanders last year unveiled a plan to reverse President Donald Trump's tax cuts for businesses and increase the corporate tax rate to 35%, up from 21%.

"We think a Bernie Sanders presidency or even the prospect that he wins the nomination probably presents one of the key risks for markets as we move through 2020," said Norman Villamin, CIO of wealth management at Union Bancaire Privee.

"That's largely because what you're going to see is, the market will have to price the prospect of rising tax rates or a reversal of the tax cuts we saw in 2018," he told CNBC's "Capital Connection" on Tuesday.

"That will be a rather major hit to earnings if the market needs to anticipate that," he added.

Villamin's comments come amid delays in the release of the results from the Iowa caucuses. The vote is seen as significant because the candidate who wins Iowa, often proceeds as the Democratic Party's presidential nominee.