Welcome to FiveThirtyEight’s six-part (!) Super Tuesday preview! Over the next several days, we’ll take you through our primary forecast state by state and district by district, highlighting which candidates are expected to win where — and why. In this inaugural article, I’ll take you on a tour of the three New England states that vote on Tuesday: Massachusetts, Maine and Vermont. Perhaps unsurprisingly for a candidate from the region, Sen. Bernie Sanders is expected to do well here. But let’s go a little deeper, as that’s not the whole story.

Massachusetts is the most competitive of these states. According to the FiveThirtyEight forecast, Sanders is a mild favorite to win, with a 3 in 5 (59 percent) chance. However, Massachusetts is Sen. Elizabeth Warren’s backyard, and we give the Bay State’s senior senator a 1 in 4 (24 percent) chance of carrying it. No other candidate’s chance of winning is in the double digits, but we can’t totally count out former Vice President Joe Biden (who has a 1 in 12, or 9 percent, chance of winning the most votes), former South Bend, Indiana, Mayor Pete Buttigieg (1 in 20, or 5 percent) or former New York City Mayor Michael Bloomberg (1 in 30, or 3 percent), who has some Massachusetts ties of his own.

Thirty-two pledged delegates to the Democratic National Convention will be allocated based on the statewide results in Massachusetts. Currently, our model is forecasting Sanders to get 26 percent of the statewide vote on average, Warren to get 19 percent, Biden to get 15 percent, Buttigieg to get 14 percent, Bloomberg to get 13 percent, Sen. Amy Klobuchar to get 7 percent, Tom Steyer to get 3 percent and Rep. Tulsi Gabbard to get 2 percent. And as you can see in the table below, our forecasts for Massachusetts’s nine congressional districts — which award between six and eight delegates each — are pretty similar.

Sanders is favored in every Massachusetts district Average forecasted vote share for the top six Democratic presidential candidates in Massachusetts congressional districts, according to the FiveThirtyEight model as of 10:30 a.m. on Feb. 28 District Sanders Warren Biden Buttigieg Bloomberg Klobuchar MA-01 26% 19% 18% 11% 15% 6% MA-02 26 19 15 14 13 8 MA-03 27 20 16 12 13 7 MA-04 25 20 13 17 11 10 MA-05 26 21 13 15 11 8 MA-06 25 20 13 15 12 9 MA-07 25 18 21 11 14 5 MA-08 25 19 15 15 12 8 MA-09 26 19 16 13 14 7 State 26 19 15 14 13 7

Sanders is expected to win every district, and Warren is expected to be the runner-up in most of them as well. In no district do we expect these two candidates to deviate more than 2 percentage points from their statewide performances.

The district-by-district variation is pretty minor for the other candidates as well — but that doesn’t mean it’s unimportant. In fact, it matters a great deal to the delegate math, since Biden, Bloomberg and Buttigieg are all hovering right around the 15-percent threshold necessary to receive any pledged delegates.

According to the model, Biden and Bloomberg have the best chance to qualify for delegates in Massachusetts’s 7th Congressional District, which covers Boston and some of its densest suburbs. This is the most establishment district in Massachusetts, based on the 2016 primary results: Former Secretary of State Hillary Clinton defeated Sanders here by more than 12 points. The 7th District is also 59 percent nonwhite, and it is the only Massachusetts district with a sizable black population, a group with which Bloomberg and especially Biden are fairly popular. In fact, we’re forecasting Biden to get 21 percent of the vote in the 7th District, which would put him ahead of Warren. Biden and Bloomberg also look like they could pick up delegates in the 1st Congressional District, a working-class district in western Massachusetts. This is the only district in Massachusetts with a college-educated population and a median household income lower than the national average.

Accordingly, Buttigieg and Klobuchar — with their white, college-educated bases — do worst in those two districts. They are more likely to excel in the tony Boston suburbs, specifically in the 4th Congressional District (Brookline, Newton, Wellesley), 5th Congressional District (Lexington, Weston, Sudbury) and 6th Congressional District (Bedford, Lynnfield, Beverly). These districts have the three highest median household incomes in Massachusetts — $84,000 a year or higher. Our model thinks Buttigieg has a shot to nab a delegate or two from these districts, but that Klobuchar is polling too low to do the same. (Not coincidentally, we are also expecting these to be among Biden’s and Bloomberg’s worst districts.)

In a nutshell, if Biden and Bloomberg don’t do well in the 1st and 7th districts, or if Buttigieg and Klobuchar don’t do well in the Boston suburbs, then it’s a bad sign for their overall prospects in Massachusetts. On the other hand, if Biden and Bloomberg do better than expected in suburbia, or if Buttigieg and Klobuchar are competitive in the 1st and 7th districts, they might be on their way to stronger-than-expected showings statewide — perhaps even enough to qualify for statewide delegates.

Up the Atlantic coast, Sanders is a solid but not overwhelming favorite in Maine — but no other candidate is particularly close to catching him. The FiveThirtyEight forecast gives Sanders a 3 in 5 (63 percent) chance of winning the Pine Tree State. The next-likeliest victor is Biden, with just a 1 in 8 (12 percent) chance. Bloomberg has a 1 in 10 (10 percent) chance, Warren has a 1 in 12 (8 percent) chance and Buttigieg has a 1 in 15 (7 percent) chance.

On average, our model forecasts that 29 percent of Maine primary voters will opt for Sanders, 16 percent each for Biden and Bloomberg, 15 percent for Warren, 14 percent for Buttigieg, 5 percent for Klobuchar and 2 percent each for Steyer and Gabbard. But the results by congressional district are arguably even more important: In fact, Maine’s 1st Congressional District is worth more pledged delegates (nine) than the state alone (eight) is! And the 2nd District is worth almost as many — seven. Here’s what our forecast says about those:

Sanders is strong everywhere in Maine Average forecasted vote share for the top six Democratic presidential candidates in Maine congressional districts, according to the FiveThirtyEight model as of 10:30 a.m. on Feb. 28 District Sanders Biden Bloomberg Warren Buttigieg Klobuchar ME-01 29% 15% 15% 15% 16% 5% ME-02 29 18 17 14 13 4 State 29 16 16 15 14 5

While both are equally monochromatic (specifically, they are more than 93 percent white), there is a stark cultural and class divide between Maine’s two congressional districts. The coastal 1st District is above the national average in terms of income and educational attainment and voted for Clinton by 15 points in 2016. Meanwhile, the interior 2nd District has seen its population and economy contract due to the decline of traditional industries such as forestry and agriculture. It is the epitome of the type of blue-collar region that deserted Democrats in 2016, going from supporting former President Barack Obama by 9 percentage points to supporting President Trump by 10.

Unsurprisingly given how their support breaks down by class, Warren, Klobuchar and especially Buttigieg figure to do better in the 1st District, while Bloomberg and especially Biden look stronger in the 2nd District. But the differences are quite small and wouldn’t normally be worth worrying about — except for the fact that, once again, several candidates are right on the cusp of 15 percent in all three jurisdictions. Even small over- or underperformances by Biden, Bloomberg, Buttigieg or Warren in Maine could affect whether they get any pledged delegates out of the state. But let’s keep this in perspective: In the grand scheme of Super Tuesday, Maine doesn’t award very many pledged delegates (24 in total).

Finally, the smallest state (with only one congressional district) to vote on Super Tuesday is Vermont. Don’t overthink this one; Sanders is expected to dominate his home state so thoroughly that any regional differences (and there were few in 2016) are unimportant. According to the FiveThirtyEight forecast, Sanders’s odds of winning are greater than 99 in 100 (99 percent). The only question is whether anyone else gets above 15 percent. Our model currently forecasts Sanders to get 57 percent of the vote, Buttigieg 11 percent, Warren 9 percent, Bloomberg 8 percent, Biden 7 percent, Klobuchar 5 percent and Gabbard and Steyer 1 percent each. If those results come exactly true, Sanders would win every single one of Vermont’s 16 pledged delegates.





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