Ben Carson 2016: Latest Polls, News and Updates on Presidential Campaign

Patrick Semansky/AP

In the first national poll of 2016, Ben Carson has continued to slip in a packed Republican field, as he sits in fourth place with 9% support among likely GOP voters. Donald Trump, meanwhile, has kept a firm lead against the crowded competition with 35%, according to the latest NBC News/SurveyMonkey poll released Tuesday.

After Trump, Texas Sen. Ted Cruz sits in second with 18%, while Florida Sen. Marco Rubio has 13%. Carson, however, has been trending the wrong way in the national polls for weeks. Since Carson had 23% support — one point behind Trump — in a poll released Nov. 4 by Quinnipiac University, he has followed it up with 16% in a Dec. 2 poll and 10% in the university's latest national poll released Dec. 22. 

Carson's drop in the polls can be partly attributed to his lack of knowledge on foreign policy, which has not only hindered him in interviews and debates, but has also made him an easy target for The Daily Show's Trevor Noah:

Carson singles out fifth-grader at campaign rally: In what can easily be summarized as a horrible idea, Carson asked a group of fifth-graders who they believed the "worst student" in their class was before talking with the kid who was singled out by his classmates during a campaign rally Thursday in Iowa.

Carson approached the iffy subject because he has repeatedly said he was considered the "dumbest person in the world" in school, which is questionable in its own right, considering he is a retired neurosurgeon. However, with a kid being singled out by his peers, Carson spoke with him after the event to try and remedy the situation. 

"So you know what we want from you, right?" Carson told the boy, according to the Washington Post. "You're going to be a neurosurgeon, OK? All right? But all you have to do to turn it around is read. I just started reading and I got to the point where it was my favorite thing in life. And it didn't take long before I knew more than all those people who said I was dumb. OK? So you do that too. OK?"

Twitter, though, was less forgiving:

Carson defends Cruz over birther issue: While some GOP candidates have used Cruz's Canadian citizenship — which he renounced 18 months ago — as an issue with his eligibility to run as president, Carson defended the senator in an interview on Newsmax TV's The Steve Malzberg Show on Thursday. 

"If your parent is a citizen of the United States, and you're born on foreign soil, you are still an American citizen," Carson said, according to BuzzFeed News. "And that has always been the case as far as I know. One of my children was born on foreign soil and they're a natural-born citizen."

Patrick Semansky/AP

Arizona Sen. John McCain had also questioned Cruz during an interview with KYFI

Cruz refuted Trump's claim in a tweet Tuesday.