It seems like 2008 all over again, with Vermont senator Bernie Sanders gaining ground on former secretary of state Hillary Clinton in the same way that President Barack Obama - then a relative unknown - came from behind to clinch the Democratic nomination.
A poll by The Des Moines Register and Bloomberg Politics, released last weekend, showed that Mrs Clinton is the first choice of 37 per cent of Democratic caucus voters in Iowa, just seven percentage points ahead of Mr Sanders.
This is reminiscent of the 2008 race, where Mrs Clinton led Mr Obama by the same margin in the barometer state in October 2007. He then overtook her in the November poll that year and went on to win the nomination.
Experts say Mr Sanders is appealing to young Democrats and first-time caucus-goers, much like Mr Obama, which is causing the Clinton campaign to sit up and take notice.
These voters may be choosing Mr Sanders, said politics professor Steffen Schmidt from Iowa State University (ISU), because "he is a powerful speaker, young voters are excited about him, I think he has some of the appeal of an 'older and wiser' guy".
"His policy positions and his anger are connecting amazingly with voters," he added.
The Iowa Poll bolsters Prof Schmidt's analysis. It showed that support for Mr Sanders was not the result of anti-Clinton sentiment - 96 per cent of respondents said they favoured Mr Sanders mostly because of who he is and his ideas, while only two per cent said they backed him because they did not support Mrs Clinton.
Also, reminiscent of Mr Obama's path to the White House, Mr Sanders is running his campaign on the support of middle-class voters, who give small donations, instead of large campaign backers.
A study by the Campaign Finance Institute shows that before Mr Obama became the Democratic nominee, 30 per cent of his war chest came from donors giving US$200 or less.
In Mr Sanders' case, small donations of US$200 (S$282) or less account for about 75 per cent of his funds (US$15.2 million as of July).
While Mr Sanders' star is on the rise, Mrs Clinton's seems to be fading in Iowa - the first state to hold caucuses and where the outcome usually provides an indication of where support lies. Support for her has dropped from as high as 56 per cent in January.
Said politics professor Mack Shelley, who chairs the political science department at ISU: "Clinton's ratings certainly have been battered by a combination of campaign errors and strength exhibited by other candidates."
He said that compared to 2008, she is "all the more likely to be perceived as a flawed 'establishment' candidate because of her time as secretary of state and the ensuing e-mail issues".
Mrs Clinton's use of a private email account has raised months of questions over transmission of classified information when she was in office.
Prof Schmidt also believes she is making a mistake by not tapping into former president Bill Clinton's "incredible charm and dynamic personality" and excluding him from her campaign.
But that is not to say that Mrs Clinton's campaign is done for. Nationally, she is still polling at 47.8 per cent for the Democratic nomination, according to political website Real Clear Politics. Mr Sanders, on the other hand, has 26.3 per cent of the Democratic vote.
Experts also point out that Mr Sanders is no Mr Obama when it comes to pulling in minority voters. "Obama was able to unify support across the spectrum of race and ethnicity, and we don't have strong evidence yet that Sanders can do that," Prof Shelley said.