Pundits said last week was former Secretary of State Hillary Clinton's best week on the 2016 campaign trail thus far, and a new poll of Iowa caucusgoers bears it out. Clinton is crushing Sen. Bernie Sanders of Vermont, coming in ahead of him by 41 points, according to the most recent Monmouth University poll, out Tuesday.

Clinton is enjoying 65 percent support in Iowa, against Sanders' 24 percent and former Maryland Gov. Martin O'Malley's 5 percent. Sanders drew startlingly close to Clinton in the most recent poll of Iowa prior to Tuesday's. However, a week during which Clinton had a strong showing before the House Benghazi Committee and in which Vice President Joe Biden announced he would not run for president seems to have blown that momentum for Sanders.

"We now have a two-person race, but one of those competitors has just pulled very far ahead," said Patrick Murray, director of the Monmouth University Polling Institute in New Jersey.

Of likely caucusgoers, a total of 40 percent indicated they had made up their mind whom to support on Feb. 1, with an additional 37 percent saying they had a strong preference. In another good sign for Clinton, 88 percent of those polled indicated they had a favorable opinion of her, which is 11 points higher than Sanders' favorable rating. She has been dogged by high unfavorable ratings for the majority of the year.

GettyImages-494328270 Hillary Clinton answering a question during the House Benghazi Committee hearing, Oct. 22, 2015. Photo: Getty

Much of Clinton's rebound is being attributed to the 11-hour Benghazi hearing last Thursday, during which she was grilled by Republicans on the Sept. 11, 2012, attacks in Benghazi, Libya, when four Americans were killed, including a U.S. ambassador. Clinton's performance, in which many said she put her accusers in their place, was widely praised. The day before, Biden, who was seen as a major potential threat to Clinton's candidacy, announced from the White House Rose Garden that he would not get into the race.

Clinton's surge in Iowa is further notable when compared to her 2008 run for president. In that race, Clinton was undercut by then-Sen. Barack Obama's electrifying speech at the Iowa Jefferson-Jackson Dinner. She dropped from a long-held first place and ultimately came in third in the Democratic caucus, with 29.5 percent of the vote, two points behind former North Carolina Sen. John Edwards. Clinton's loss pulled her into a long nominating battle with Obama that she eventually lost. This year's Jefferson-Jackson Dinner took place Saturday.