Democrats fret as polls show Bernie Sanders surging in early primary states

A fresh batch of polls show Sen. Bernie Sanders (I-Vt.) starting the new year with a surge in the 2020 Democratic primary race.

According to the CBS Battleground Tracker survey, Sanders finds himself in a three-way tie with former Vice President Joe Biden and South Bend Mayor Pete Buttigieg, each at 23 percent, among caucus-goers in Iowa. Sens. Elizabeth Warren (Mass.) and Amy Klobuchar (Minn.) find themselves in a distant fourth and fifth places, respectively.

The FiveThirtyEight average of Iowa surveys finds a similar scenario with Biden slightly ahead of Sanders and Buttigieg, well within a polling margin of error.

Meanwhile, in New Hampshire, the Vermont socialist leads the field with 27 percent support among the state's primary voters. He is closely followed by Biden at 25 percent, and Warren at 18 percent. Sanders' lead in CBS' poll is consistent with a RealClearPolitics average of surveys showing him with a four-point advantage in the Granite State.

Sanders' voters are the most enthusiastic

The CBS survey also found that Sanders' supporters are, by far, the most enthusiastic of any of the Democratic candidates, an important factor in tight races. Among voters who said they intend to back him in the Iowa caucuses, 67 percent said they were "enthusiastic" to support him, compared to 49 percent who said the same about Biden.

Similarly, in New Hampshire, 65 percent of Sanders' called themselves "enthusiastic" about supporting him, surpassing all other candidates, and were more certain in their voting decision. Nearly half (47 percent) of Sanders' New Hampshire backers said they've definitely made up their minds while only 15 percent of Biden's supporters said the same.

One possible problem for Sanders in Iowa, though, is that his campaign relies more heavily on first-time caucus goers, with 36 percent of his supporters saying this would be their first caucus, compared to Buttigieg's 25 percent and Biden's 24 percent. This is important, as the state's unique caucus system relies heavily on organization which may favor more experienced voters.

Democrats worry Sanders cannot beat Trump

Sanders' electoral resilience is worrisome to Democrats who prioritize beating Trump in the general election above policy and ideological considerations. As a May 2019 poll showed, 65 percent of Democratic voters said that taking back the White House in 2020 was their top concern.

However, voters are unsure if Sanders can beat the president. Democrats in Iowa and New Hampshire alike said that Biden has a better chance of winning the general election. Additionally, half or more of the voters in both states told CBS' pollsters that Sanders' policy were "too progressive" for winning over swing voters.

The Iowa caucuses is scheduled for Feb. 3, followed by the New Hampshire primary on Feb. 11.