Former U.S. Secretary of State Hillary Clinton listens to Sen. Bernie Sanders of Vermont at the Democratic presidential candidates' debate at St. Anselm College in Manchester, New Hampshire, Dec. 19, 2015. Reuters/Brian Snyder

Hillary Clinton may be the presumptive presidential nominee for the Democratic Party, but a new fundraising email shows she’s not so sure she has it in the bag. Just days after a separate fundraising note admitted to supporters that she could lose the nomination, Clinton looked to drum up cash for the campaign again by saying that if she loses either of the first two nominating states in February, it will be a long and dreary primary season.

"If we lose Iowa or New Hampshire," the subject line of the email reads before continuing in the body of the message. "The contests in Iowa and New Hampshire will be here faster than you can believe (or at least faster than I can!). That means it's time to be realistic about the resources we still need to be ready because right now, winning this nomination is no sure thing." The email concludes by asking for a $1 donation.

Her email also comes hours following a new CBS/Yougov poll that showed her lead in the Iowa caucuses, the first nominating contest of the season, had dropped to just five points ahead of her closest rival, Sen. Bernie Sanders. In New Hampshire, the second state to choose its preferred presidential candidates, Sanders has been widening a lead over Clinton for the past month and currently maintains a lead of 8.6 points in averages of national polls from Real Clear Politics.

Hillary Clinton vs Bernie Sanders - RCP Poll Average | InsideGov

Fundraising letters inherently do not provide clear insight into the private thoughts of the campaign. It’s possible that the campaign is just looking to scare supporters into giving her money and valuable voter contact data in the process. Considering her slipping polling in the first two nominating states, however, the new emails may very well reflect some anxiety in Clintonland.

Given her surprise loss to soon-to-be President Barack Obama in Iowa nearly eight years ago, which interrupted what she hoped would be a straight march to the nomination, that concern could be well-grounded. She did, however, beat Obama nearly a week later in New Hampshire — a surprise of its own for the Obama camp.

At any rate, Clinton and Sanders have starkly different approaches to fundraising. Clinton's campaign committee has raised $77.5 million so far in the campaign, according to data from the Center for Responsive Politics. Sanders' has raised $41.5 million. However, the vast majority of Clinton’s campaign cash (81 percent) comes from large donors who gave $200 or more. Sanders, on the other hand, has proved to be much more adept at raising small amounts of cash from a lot of people and can boast that 74 percent of his donations were from the types of small donors Clinton is appealing to in her emails.