Pollster Lee Miringoff said in an interview that aired Thursday on "What America's Thinking" that the structure of the U.S. electoral system makes it "all but impossible" for independent candidates to win the White House.

Miringoff, director of the Marist Poll, noted that it is difficult for independent candidates to secure a majority of votes in the Electoral College to win the presidency. Political parties in each state generally choose electors.

"They can have a huge impact, but the structure of American politics make it all but impossible for an independent to actually win because you have to get a plurality in enough states to get to 270 electoral votes," he told Hill.TV's Jamal Simmons.

"Occasionally a third party candidate gets some electoral votes," he added, but noted "that's even rare."

Former Starbucks CEO Howard Schultz has garnered considerable attention since announcing Sunday that he is considering running for president in 2020 as an independent.

Various Democrats, including 2020 contender Julián Castro, have slammed the idea, saying Schultz's candidacy would split the Democratic ticket, ensuring a victory for President Trump Donald John TrumpUS reimposes UN sanctions on Iran amid increasing tensions Jeff Flake: Republicans 'should hold the same position' on SCOTUS vacancy as 2016 Trump supporters chant 'Fill that seat' at North Carolina rally MORE.

"I think the concern for the Democrats is not that this guy is going to start carrying states, it's that he's going to do the Ralph Nader, the Jill Stein, he's going to siphon off votes in different places [where] he can have an impact," Miringoff said.

— Julia Manchester