Nearly one in five Democrats — almost 20 percent — said they would switch sides and vote for Republican presidential frontrunner Donald Trump, according to a new poll.

Republican presidential candidate Donald Trump addresses supporters at a rally, Saturday, Jan. 9, 2016, in Ottumwa, Iowa. (AP Photo/Jae C. Hong)

Republican presidential candidate Donald Trump addresses supporters at a rally, Saturday, Jan. 9, 2016, in Ottumwa, Iowa. (AP Photo/Jae C. Hong)

And even though the poll shows 14 percent of Republicans say they would vote for Hillary Clinton, a much greater percentage of Democratic voters say they’re “100 percent sure” of going for Trump than their Republican counterparts.

U.S. News & World Report outlined the survey by Washington-based Mercury Analytics, which was partly an online questionnaire and partly a first-blush response to Trump’s first big campaign ad — and it was administered to 916 self-proclaimed “likely voters” mostly on Wednesday and Thursday with a margin of error of plus or minus 3.5 percent.

Mercury Analytics said “the primary messages of Trump’s ad resonated more than Democratic elites would hope,” the magazine reported.

“We expected Trump’s first campaign spot to strongly appeal to Republican Trump supporters, with little impact – or in fact negative impact – on Democratic or independent voters,” Mercury CEO Ron Howard, a Democrat whose firm works for candidates in both parties, told the magazine.

“The challenge to Hillary if Trump is the nominee and pivots to the center in the general election as a problem-solving, independent-minded, successful ‘get it done’ businessman,” Howard continued to the magazine, “is that Democrats will no longer be able to count on his personality and outrageous sound bites to disqualify him in the voters’ minds.”

(H/T: Drudge Report)