On Saturday, Sen. Elizabeth Warren picked up her second newspaper endorsement of the week: The Des Moines Register announced it’s endorsing Warren in the Iowa caucuses. Sen. Amy Klobuchar also picked up her second newspaper endorsement with the New Hampshire Union Leader endorsing her on Saturday, which could help Klobuchar in the Granite State, but like Warren, she needs a strong finish in Iowa first.

And right now, Iowa is a four-way traffic jam. We’ve gotten a flurry of new polls this weekend (that we’ll be writing about more soon), but as of this morning, Warren is in fourth place in our Iowa polling average with 15 percent support — 7 percentage points behind Sanders and Biden, who are essentially tied for first at 22 percent, and about 4 points behind former South Bend, Indiana, Mayor Pete Buttigieg, who’s polling at roughly 19 percent. (Klobuchar, meanwhile, is at 8 percent.)





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Warren’s odds of winning Iowa are a bit lower than other candidates in our forecast — she’s only got about a 1 in 9 shot compared to Biden and Sanders’s 1 in 3 shot, but she’s also not that far behind (Buttigieg has a 1 in 4 chance). The good news for Warren is that the Des Moines Register’s endorsement has historically given its recipient a boost in the polls — though we should be careful not to overstate its importance.

But on average, since 1988, when the paper first began endorsing candidates before the caucuses, candidates have gotten about a 4-point boost from where their polling average in Iowa was before the endorsement to how they ultimately fared in the caucuses (their vote share), according to historical polling average data from FiveThirtyEight’s forecast model.

The Des Moines Register endorsement helps at the margins The polling average and actual vote results for candidates in the Iowa caucuses who were endorsed by the Des Moines Register YEAR PARTY CANDIDATE Polling Avg Before Endorsement ACTUAL VOTE CHANGE 1988 D Paul Simon 16.7% 26.7% 10.0 1988 R Bob Dole 43.0 37.4 -5.6 1996 R Bob Dole 34.0 26.3 -7.7 2000 D Bill Bradley 30.6 36.6 6.0 2000 R George W. Bush 46.1 41.0 -5.1 2004 D John Edwards 11.0 32.6 21.6 2008 D Hillary Clinton 27.8 30.4 2.6 2008 R John McCain 6.1 13.1 7.0 2012 R Mitt Romney 19.5 24.5 5.0 2016 D Hillary Clinton 47.7 49.8 2.1 2016 R Marco Rubio 11.6 23.1 11.5 Average 4.3 Source: Polls, Dave Leip’s Atlas of U.S. Presidential Elections, Des Moines Register

And overall, eight of the 11 candidates the paper endorsed did do better than we expected them to do before getting the endorsement, including all six Democrats. (By contrast, the endorsement has been a bit more of a mixed bag for Republicans, with only half seeing a boost in their numbers.) So in a race this close, the paper’s endorsement could really help Warren.

In fact, if we dig a little deeper, the data suggests that the Register’s endorsement may matter a lot more to candidates like Warren who are polling below 20 percent in Iowa. We found those candidates gained, on average, 11 points between their pre-endorsement polling average and final vote share tally. Conversely, candidates polling higher than 20 percent actually saw their vote share tick down by about a point, on average.

Warren will probably be hard-pressed to surpass Sen. John Edwards’s nearly 22-point bump in the Democratic caucuses in 2004, where he jumped from 11 percent to 33 percent, but even a 10-point increase like the one Sen. Paul Simon got in the 1988 Democratic contest could be a gamechanger. Granted, neither of those candidates ultimately won the caucuses, but both Simon and Edwards got solid second-place results — and in a race this crowded, who finishes second could be pretty important.

It’s difficult to say just how much the Register’s endorsement could help Warren, as in our digital age, newspapers have an ever-shrinking footprint in the media landscape. But the Register is Iowa’s largest paper and a lot of Iowans still haven’t made up their minds. An Iowa poll released on Saturday by the New York Times Upshot/Siena College found that 39 percent of likely caucus-goers could be persuaded to back a different candidate. So for Warren, a substantial bump in coverage — particularly with an upbeat framing — could matter quite a bit as media coverage and candidate poll performance tend to be correlated, and that boost might provide just enough of a bump to find victory — or at least a solid second-place finish — on Feb. 3.