DURHAM, N.H.—While polls predicting the outcome “if the election were held today,” are popular with pundits and candidates alike, seasoned pollsters warn that “it ain’t over till it’s over,” according to a new analysis released by the Carsey School of Public Policy at the University of New Hampshire.

“Leading up to the election, anywhere between half and three-quarters of voters are still trying to decide whom to choose,” the researchers said. “That means that last-minute swings in support are quite possible and quite common.”

The researchers also noted that heading into the 2020 New Hampshire primary, 57% of Democrats still had not decided who they would vote for and even those who claim to be “decided” can change their mind at the last minute.

“In a primary contest, there is no party difference to anchor voter preferences,” the researchers said. “Policy differences among candidates tend to be so slight that the voter could just as easily vote for one candidate as another. Thus, last-minute ads, news stories, and campaign activities that suddenly favor one candidate over another could cause a major swing in voter preferences in just a short time.”

The research was conducted by David Moore, founding director of the UNH Survey Center and a Carsey fellow; and Andrew Smith, director of the UNH Survey Center. They are coauthors of “The First Primary: New Hampshire’s Outsize Role in Presidential Nominations.”

The Carsey School of Public Policy is nationally recognized for research, policy education and bringing people together for thoughtful dialogue to address important societal challenges. The school develops and facilitates innovative, responsive and equitable solutions at all levels of government and in the for-profit and nonprofit sectors.

The University of New Hampshire inspires innovation and transforms lives in our state, nation, and world. More than 16,000 students from all 50 states and 71 countries engage with an award-winning faculty in top-ranked programs in business, engineering, law, health, and human services, liberal arts and the sciences across more than 200 programs of study. As one of the nation’s highest-performing research universities, UNH partners with NASA, NOAA, NSF and NIH, and receives more than $110 million in competitive external funding every year to further explore and define the frontiers of land, sea, and space.