The finance professor who correctly called the Dow Jones industrial average's surge to 20,000 said he expects stocks to jump even higher in the last 101 days of the year.

The Wharton School's Jeremy Siegel believes it'll have a lot to do with President Donald Trump's intention to get business-friendly reforms passed on Capitol Hill — not the latest Federal Reserve decision on interest rates or better-than-expected economic growth figures.

"I would say corporate tax reform could add another 10 percent to the market even this year," Siegel said Wednesday on CNBC's "Trading Nation." A deal "looks very likely to get done."

It's the second time in less than 12 months that Siegel, a longtime bull, has made a bold market call. And it came on a day when the Dow and closed at record highs.

In the final weeks of 2016, Siegel argued that the blue chip stock index was very close to hitting the 20,000 milestone. It broke through that key psychological level on Jan. 25 and since then has soared more than 10 percent.

If Siegel is right this time, too, a 10 percent jump would put the Dow around 24,650 and the S&P 500 at 2,760 based on Wednesday's closes.

"There's new hope that taxes really have a chance to be done. I remained steadfast throughout some of the bleak days in the last few months when no one thought anything could be done," Siegel added.

"There's a little bit more optimism now. I think a corporate tax deal will be done, and I think that will be positive for the equity market," he said.