With just over three weeks to go until the Iowa Caucuses, the Democratic race is starting to get very interesting. One thing is clear: Hillary Clinton has lost momentum — and this is the worst possible time to lose it.

Today, Al Hunt at Bloomberg, and the latest update from Rasmussen Reports, provide a state of play on the Democratic side. Both sources indicate trouble for the Clinton campaign. And, let’s be realistic. Any candidate who has lost momentum now is unlikely to regain it before Christmas or New Years. All the talk of inevitability about Clinton — which some would say was her greatest asset — is fading rapidly. That doesn’t mean that she’s going to lose, it just means that a once-sure-thing is no longer certain.

Hillary Clinton has been the frontrunner — and is the closest thing to an incumbent in the race for President on either side. It’s hard for me to understand how anyone who doesn’t support Clinton now will somehow learn something new about her that will garner their vote between now and early January. On the other hand, it seems that since late October, voters have been learning things they don’t like about Hillary Clinton — or are having doubts about her confirmed.

Al Hunt appears to think the Clinton campaign is in trouble. According to his sources, the campaign may be in for a staff shake-up. Not the kind of leaks that help a campaign three weeks out. And, the word “imploded” is never helpful:

The Clinton organization had a clear plan A: It envisioned the candidate, as the choice of the party establishment and natural heir to the presidency, to so dominate 2007 that she would be able to corner, not have to capture, the nomination. It worked perfectly for most of the year. The strategy has imploded.

From Rasmussen Reports comes a similar analysis with state-specific polling data to back it up:

Ultimately, however, it’s not the numbers that make the race seem different. What’s changed is the Clinton campaign. Up until the night of October 30, the former First Lady’s campaign had been a textbook model of a disciplined campaign following a clear game plan. Then, famously, the candidate stumbled on a question about drivers’ licenses for undocumented workers. But, it wasn’t the debate answer that caused problems as much as the campaign’s response to it. A week later, on CNN, Clinton still couldn’t answer the question directly. A story that should have been handled in a day with a clarification and a new story line became the new narrative of the race. Since then, it seems that every news cycle has a bit of bad news for candidate Clinton. Her strategy of going negative on Obama has raised more eyebrows than support. From a polling perspective, the most damaging recent news may be found in the Rasmussen Reports South Carolina poll. Earlier in the campaign, Clinton and Obama were evenly splitting the African-American vote. But, now, Obama has opened a wide lead in that demographic. If that same change is repeated throughout the South, Obama’s prospects have brightened considerably. What does it all mean? The voters of Iowa will begin to answer that question on January 3. Until then, just like last week, all that can be said with certainty is that the race is getting closer.

A lot of people are trying to figure out what it all means. We’ll know for sure in early January. Clearly, there is concern over at the Clinton camp, because Hillary’s guru, Mark Penn, felt it necessary to provide his spin on the polls over at the Clinton blog. (He’s more optimistic than Hunt or Rasmussen).

Now, if any campaign staff is capable of turning this one around, it’s Team Hillary. But, then again, Team Hillary got themselves into this mess. So unless someone turns around Team Hillary first, we may be seeing an upset.