(CNN) Donald Trump's eldest son said Wednesday night that his father's unlikely pursuit of the presidency represented a "step down" from the Republican nominee's business career.

"Unlike Hillary Clinton, who's gotten very rich being a politician, peddling American influence, he hasn't -- this is only a step down," Trump Jr. told Fox News following the third and final presidential debate in Las Vegas.

Trump Jr. added that his father wanted to ensure that "all Americans, all ethnicities and backgrounds have the same opportunities to do what he's been able to do" in business.

The candidate's son, who emerged early in the campaign as one his most fierce surrogates, has stumbled repeatedly under the glare of the general election spotlight.

In late September, Trump Jr. set off a minor furor when he compared Syrian refugees to Skittles candy.

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