Democratic socialist Bernie Sanders, an Independent candidate from Vermont whose platform of government if elected U.S. president will focus on reversing economic inequality, and former vice president Joe Biden, remain the favorite to win the Democratic Party's upcoming Iowa caucus on February 3.

The Iowa caucuses for both Democrats and Republicans are noteworthy as the first major contest of the United States presidential primary season. The U.S. presidential election takes place November 3.

Sanders says he's "running for president so that, when we are in the White House, the movement we build together can achieve economic, racial, social and environmental justice for all."

A new NBC/WSJ poll released Friday morning shows Sanders, 78, receiving 27% of the vote among Iowa caucus goers. He's barely ahead of Biden, 77, with 26% of the vote. Behind Biden is Sen. Elizabeth Warren (D-MA) with 15%; former New York City mayor Mike Bloomberg with 9%; Mayor Pete Buttigieg with 7%; Sen. Amy Klobuchar (D-MN) with 5% and businessman Andrew Yang with 4%.

Sanders' supporters, who are widely seen as the most fervent among all Democrats, say they'll definitely support him. Sixty percent of Sanders' supporters say they'll vote for Bernie compared to Biden's supporters, only 48% of whom say they'll support him. In addition, a third of Democratic primary voters admit to being "enthusiastic" about Sanders compared to 26% who say the same about Biden and Warren.

A New York Times/Siena College conducted from Jan. 20 to 23 and released Thursday also shows Sanders winning Iowa. Sanders is the first choice among Iowa Democrats as the party's presidential nominee with 25% of them saying so. Buttigieg, 37, who keeps being criticized for his political inexperience, was the choice of 18% of Iowa Democrats while Biden took 17%.

Surprisingly, old man Sanders is the candidate of younger Democrats. Sanders leads among Iowa voters under 30, and is supported by 40% of this demographic. Only nine percent of Sanders' peer age group, or voters 65 and older, support him. Biden is the bet for 32% of those over 65 but receives only 10% support among the youngest Iowa caucusgoers.

On the other hand, a CNN Poll of Polls released Friday shows Biden ahead of Sanders going into Iowa. Biden averages 27% support among registered Democrats and Democratic-leaning independents or likely Democratic voters. Sanders averages 24%.

Warren averages 14%, Bloomberg, 8%; Buttigieg, 7%; Klobuchar, 5%; Yang, 4%, and businessman Tom Steyer, 2%.

The CNN Poll of Polls is an average of the six most recent nonpartisan, live operator, national surveys on the race for the Democratic presidential nomination conducted among potential Democratic voters.

It includes NBC News/Wall Street Journal poll conducted Jan. 26-29; the Quinnipiac University poll conducted Jan. 22-27; the Fox News poll conducted Jan. 19-22; the Washington Post/ABC News poll conducted Jan. 20-23; the Monmouth University poll conducted Jan. 16-20 and the CNN poll conducted by SSRS from January 16-19. The Poll of Polls does not have a margin of sampling error.