"Electability", or eligibility in Swedish, is about appealing to as many groups as possible at the same time. And that can determine who becomes the Democratic presidential candidate.

Conclusions about "electability" mean that some voters do not vote for the person they would prefer to see as the Democratic presidential candidate, but the one they believe appeals the most and thus has the greatest chance of winning over Trump.

Sanders and Warren can be difficult to choose

For example, it is discussed by assessors whether it is a problem for Bernie Sanders that he openly calls himself a socialist and that in that case it could scare away voters.

Both Sanders and Elisabeth Warren advocate a ban on fracking, a method of extracting gas from the ground that has given life to the American gas industry over the past decade. This is seen as something that can affect their eligibility.

When the voter Leah Marth is interviewed by the Reuters news agency in the state of Iowa in connection with the primary elections, she declares that she will not vote for her favorite Elisabeth Warren.

- It's to get rid of Trump. Had it been another year, I would be on her side, she tells Reuters.

Election requires a new way of thinking

Birgitta Ohlsson (L), communications consultant and former EU minister, among others, follows the election closely. She says that in most cases, you choose your favorite based on the nuances between the candidates.

- Now the unifying factor is who can beat Trump. It provides completely different conditions that one must consider.

Bid's strongest argument - eligibility

Democratic presidential candidate and former Vice President Joe Biden and his wife Jill are campaigning in Nashua, New Hampshire.

The candidate who is highlighted just for his eligibility is Joe Biden, which he uses himself as an argument for being elected presidential candidate.

"You have to win, you have to be able to beat Trump and there must be electoral Democrats in the states we need to win in," Joe Biden said during his visit to Manchester, New Hampshire, CNN reports.

But Biden's placement after the Iowa nomination meeting can get people thinking. In the analysis for the latest edition of the Quinnipiac University Poll study, from Quinnipiac University in Connecticut, analyst Tim Malloy notes that this image of Biden is faltering.

"It is obvious that Biden's fourth place in Iowa has damaged the perception of what was his greatest strength - eligibility," he says in the report.

Decency important for eligibility

Birgitta Ohlson also believes that what constitutes eligibility may also be about decency when Democrats choose who will face Trump in the election.

- Donald Trump has lowered the threshold of decency, not only in the US, but also globally. So I think many, even Republicans, are pretty much yearning for a person who will be a contrast on that front, she says.