According to U.S. News & World Report,

A new survey of likely voters might at least raise momentary dyspepsia for Democrats since it suggests why it wouldn’t be a cakewalk.

The survey by Washington-based Mercury Analytics is a combination online questionnaire and “dial-test” of Trump’s first big campaign ad among 916 self-proclaimed “likely voters” (this video shows the ad and the dial test results). It took place primarily Wednesday and Thursday and has a margin of error of plus or minus 3.5 percent.

Nearly 20 percent of likely Democratic voters say they’d cross sides and vote for Trump, while a small number, or 14 percent, of Republicans claim they’d vote for Clinton. When those groups were further broken down, a far higher percentage of the crossover Democrats contend they are “100 percent sure” of switching than the Republicans ….

Mercury CEO Ron Howard, a Democrat whose firm works for candidates in both parties and corporate clients, concedes, “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.”

He continues, “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 is that Democrats will no longer be able to count on his personality and outrageous sound bites to disqualify him in the voters’ minds.”

If Trump gets the Republican Party nomination, this could be an even more interesting election than anybody anticipated. There hasn’t been a large crossover of Democrats to the Republican candidate since Ronald Reagan in 1980, who was supported by many “blue dog” Democrats.