President-elect Donald Trump's victory is the sole reason the market is hitting new highs, and the rally "has a while to go," Wharton finance professor Jeremy Siegel told CNBC on Tuesday.

"When you have all the smalls stocks, large stocks, even tech stocks — which we know have had some challenges — joining with it, I don't think this is something that ends tomorrow. I think it continues through December," he said in an interview with CNBC's "Closing Bell."