Has the tide swung back to Hillary Clinton in Iowa? Or is the latest poll of likely caucus-goers simply more evidence that the 2016 cycle has become impossible to pin down? The Hill reports on the Emerson College poll that puts Hillary up by nine over Bernie Sanders:

Clinton leads Sanders by 9 points in an Emerson College Polling Society survey released late Thursday.

She takes 52 percent to Sanders’ 43 percent among likely Democratic primary voters in the Hawkeye State.

Clinton also owns an advantage over Sanders among Iowa’s registered Democrats, pollsters found. The former secretary of State takes 54 percent to his 42 percent.

Sanders sneaks past Clinton in support among Democratic-leaning registered independents, however. He leads 44 percent to the former first lady’s 36 percent.

Emerson College’s release covers the results for both parties:

In a new statewide poll, Hillary Clinton and Donald Trump have surged to 9- and 10- point leads, respectively, in Iowa with just 10 days before the state’s first-in-the nationvoting begins. Clinton receives 52% of the Democratic vote and Sanders 43%. Trump leads his Republican rivals with 33%, followed by Ted Cruz at 23%. Marco Rubio (14%) and Ben Carson (9%) round out the top four, with the rest of field under 6%. Rick Santorum−who won the 2012 Iowa GOP Caucus with 25% of the vote−has less than 1% of Iowans this time around, and Mike Huckabee, who won it in 2008, is at 2%.

The survey began January 18, the day after the latest Democrat debate, and concluded January 20, the day following Sarah Palin’s endorsement of Donald Trump.

“At this point, while both Trump and Clinton have significant leads in their own primaries the electorate appears volatile, and it is still up in the air as to who will win,” said Henry Krause, a Senior Political Communication major at Emerson College, who helped oversee the project. The data for both parties’ candidates fluctuated on the three days of polling. Clinton held a 14-point lead over Sanders on Monday, dropped to 9 points on Tuesday and was down to a 1-point margin (48% to 47%) on Wednesday. Trump also saw variability over the three day, watching a 13-point lead on Monday drop to 4 points on Tuesday and then rebound on Wednesday to 12 points, 35% to 22%, over Cruz.

The first hint that something has gone off the rails is in the favorability ratings:

Iowa voters are not thrilled with their 2016 Presidential options. The top three GOP candidates all have negative favorability numbers, with Trump at 37% favorable to 55% unfavorable, Rubio at 37% favorable to 47% unfavorable and Cruz even worse at 34% favorable to 54% favorable. Clinton has the highest favorable rating (42%) among the top contenders but also carries a high unfavorable rating of 53%.

There may be a small probability that these results reflect reality, but don’t put money down on it. All other polling in the race shows Rubio’s favorability to be either positive or very nearly so, while Cruz’ has improved significantly since the beginning of the primary fight a year ago or so. If there has been another poll showing Hillary with the highest favorability in the field, I certainly can’t recall it. Also, Emerson curiously didn’t poll on Bernie Sanders’ favorability, or if they did, they didn’t include the results in the data they released. Curious, especially since they polled for three Republicans on the same issue.

Also, the sample here appears to be a little off. The D/R/I is 40.5/41/18.5, which has just about the right relationship between Democrats and Republicans in a presidential general election, but seems to be pretty low on independents, who comprised 34% of 2012 general-election voters in Iowa. It’s possible that independents will turn out lower for the caucuses, but even when the Republican caucus was the only game in Iowa four years ago, 23% of the caucus-goers were independents. With the nominations for both parties in play, one would expect a higher percentage of independents in the mix. Given that this same poll shows Sanders scoring an advantage among independents (44/36), an under-representation matters.

On the other hand, recent polls have shown mixed results, too. Sanders got 51/43 in CNN’s poll, but Hillary led two others by nine and 21 points over the past ten days. (Trump’s 10-point lead is almost exactly the same as the 11-point lead he got from CNN, though.) Another nine-point lead isn’t necessarily going to be an outlier — but that doesn’t mean it reflects reality, either. While the “Hillary goes back into the lead!” meme makes for a good headline, I wouldn’t base a conclusion like that on this poll. The RCP average for this contest shows a virtual tie between Sanders and Clinton, and I suspect that’s closer to the mark.