midterm elections
A Kansas resident fills out his ballot for the midterms on the first day of in-person voting at the Douglas County Clerk Election Office in Lawrence, Kansas on October 14. Getty Images

A new survey has revealed what voters fear most will happen if their side loses the upcoming midterm elections.

The CNBC poll found that Democrats worry that President Donald Trump would have unchecked power, while Republicans worry Democrats will pursue extreme policies.

Republican voters also expect higher taxes and weaker border security should they lose the election. If Republicans win, Democrats fear Trump will continue hard line immigration enforcement and military activities in Iran.

"That totally shows the polarization ... and the fear that one side is going to completely undo the agenda of the other," Ron Bonjean, a Republican strategist and co-founder of ROKK Solutions, told CNBC. "What Republicans are worried about is that Democrats are going to go back to the way it was during the Biden administration."

Despite Democratic fears, the party appears on a path to at least win the House. A recent analysis by Cook Political Report found that Democrats were likely to win a House majority, and the bigger question now was how large that majority would be.

"Republicans' path to keeping control of the House has all but evaporated. The outstanding question is how large Democrats' majority will be in 2027; in the best-case scenario, their party could enter the new Congress with more seats than they had after successfully flipping control of the House in 2006 and 2018," the analysis stated.

Sabato's Crystal Ball is even more optimistic for the Democrats. The nonpartisan political analysis website currently has 223 races as at least "lean" Democrat and about 200 as at least "lean" Republican, with about 12 tossups.

"The trend toward a more substantially-sized Democratic House majority seems clear. What that would actually mean in terms of seats remains a question mark," the site states. "A good measuring stick is 2018, when Democrats ended up winning 235 House seats. Forced to choose today, we probably wouldn't quite put the Democrats there, but we think they'll get close to that number and could exceed it."

The Senate is less of a clear picture. Although Democrats have a chance to win a Senate majority, the races still structurally favor Republicans because many of the competitive seats are in areas that have traditionally voted Republican.

"Broadly speaking, there are not really any clear signs of a Republican recovery. The basic structure of the Senate map does still give Republicans clear avenues to hang on to their majority even if their position as the Senate favorite has evaporated over the course of the cycle," the site stated.