Trump, the 69-year-old New York-based real estate tycoon, has a support of 39 per cent of the Republican and Republican leaning voters, according to the CNN/ORC poll.
Texas Senator Ted Cruz, his closest competitor, has gathered 18 per cent of the votes.
The poll indicates that his recent anti-Muslim rhetoric and comments against Democratic presidential frontrunner Hillary Clinton has had no impact on the popularity of Trump, who announced to join politics only this summer.
Both the polls were conducted after the latest Republican presidential debate last week.
Earlier this month, Trump called for "a total and complete shutdown" of Muslims entering the US in the aftermath of the California massacre, the most divisive remarks yet by the Republican presidential frontrunner that drew widespread global condemnation including from his party's rival candidates and the White House.