Our Final Forecast For Arizona, Florida And Illinois Shows A Big Biden Lead

In an extraordinary move, Ohio postponed its primary election at the last minute due to concerns about COVID-19, meaning just three states will vote today — Arizona, Florida and Illinois, the latter two of which are among the 10 most delegate-rich contests in the Democratic presidential primary.

But despite the bumps in the road, the Democratic nomination race continues, which means it’s time for FiveThirtyEight to once again freeze its forecast to see what the outlook is in each state. (Remember, we won’t be adding any new polls, endorsements or other data to our forecast until we have results from tonight’s contests.)

Overall, the top-line outcomes in these three states are pretty straightforward: Former Vice President Joe Biden is the heavy favorite, with a greater than 99 percent chance of winning the most votes in each state, according to our forecast. On average, Biden is projected to win anywhere from 59 percent to 67 percent of the vote, which doesn’t leave Sen. Bernie Sanders with much of a shot in any of these states.

The main thing to watch tonight will be the margins between Biden and Sanders, as these will directly affect the delegate race. Blowout wins for Biden could also push the race toward its de facto conclusion and may even prompt Sanders to drop out. Although this scenario is unlikely, we shouldn’t completely write off an election surprise, especially considering we don’t know how the COVID-19 virus may affect these elections.

Coming into Tuesday, we have plenty of polling from Florida (12 polls), but in Arizona and Illinois, we only have six or fewer polls conducted entirely after Super Tuesday. The polls we do have, though, largely tell the same story: Biden is ahead and often by double-digit margins. Let’s run through what the surveys conducted since Super Tuesday say about the race in each state, starting with Florida (from most recent to oldest):

• The final looks at the Florida contest come from Swayable and AtlasIntel, which both found Biden way up. Swayable’s survey showed Biden leading Sanders by 39 points, 64 percent to 25 percent. AtlasIntel’s poll similarly found Biden up 40 points, 67 percent to 27 percent. And after adjusting for the pollster’s house effects, or the tendency for a pollster to consistently poll better or worse for one candidate, the model treated the AtlasIntel survey as a 43-point lead for Biden. (The Swayable poll’s margin didn’t shift.)
• Point Blank Political has taken two looks at the Democratic race in Florida since Super Tuesday, and its most recent survey, conducted March 11 to 13, found Biden ahead of Sanders by about 28 percentage points, 57 percent to 29 percent. This was largely in line with the pollster’s earlier poll, conducted right after Super Tuesday, which found Biden up by about 26 points. Once we adjusted for house effects, these polls were even more favorable for Biden, putting his margin at 36 points instead of 28 in Point Blank Political’s most recent poll and at 33 points instead of 26 in its older poll.
• A poll from Emerson College found Biden leading Sanders by 38 points, 65 percent to 27 percent. And because Emerson has usually had pretty strong numbers for Sanders, the model treated this poll as a 42-point margin for Biden, after adjusting for house effects.
• Another survey from Gravis Marketing conducted March 10 to 12, put Biden ahead by 41 points over Sanders, 66 percent to 25 percent. Latino Decisions was similarly bullish on Biden, as its Florida survey found Biden up by 38 points, 63 percent to 25 percent. Neither poll changed much after adjusting for house effects. The same was true of a survey from the University of North Florida, which gave Biden a 44-point edge over Sanders, 66 percent to 22 percent. ROI Rocket found Biden ahead by 40 points, 67 percent to 27 percent, which shifted to a 42-point Biden lead after adjusting for house effects.
• St. Pete Polls has polled the Florida race twice since Super Tuesday, and its most recent survey found Biden ahead of Sanders by about 55 points, 69 percent to 14 percent, with drop-out candidates winning most of the remaining vote. This was an 8-point increase for Biden from St. Pete Polls’s earlier March poll, although the gap between Biden and Sanders in the newest poll narrows to 47 points after adjusting for house effects. Florida Atlantic University also polled the Florida primary and found Biden up by 36 points over Sanders, 61 percent to 25 percent, and that margin doesn’t move much after accounting for house effects.

We don’t have as much polling to work with from Arizona and Illinois, but the surveys in those states also agree that Biden is well ahead of Sanders. Here’s what the polls say:

• In Arizona, Swayable found Biden ahead of Sanders by 24 points, 53 percent to 29 percent, a margin that didn’t really change because of house effects. Meanwhile, NBC News/Marist College’s survey found Biden up just 17 points over Sanders. But Marist has been a bit friendlier to Sanders than some other pollsters, so after adjusting for house effects, the model treated this poll as Biden ahead by 20 points. Latino Decisions also found Biden leading Sanders by 17 points, 51 percent to 34 percent, which doesn’t move much due to house effects. Another poll from Monmouth University on Monday showed Biden ahead by 20 points, 51 percent to 31 percent, and that result barely budged after considering house effects.

• In Illinois, Swayable also took a final look and found Biden leading Sanders by 34 points, 63 percent to 29 percent, which didn’t change much after adjusting for house effects. Emerson College found Biden up by 21 points over Sanders, 57 percent to 36 percent, but after adjusting for Emerson’s pro-Sanders lean, the model treated Biden as up by 25 points in this poll. ROI Rocket polled here as well and found Biden up 23 points, 57 percent to 34 percent, which the model treated as a 25-point lead after adjusting for house effects. Gravis Marketing showed Biden ahead by 38 points (a 63 percent to 25 percent edge over Sanders), which didn’t shift much due to house effects. Victory Research found a somewhat closer race, with Biden up 55 percent to 36 percent, though after adjustments Biden led by 21 points. Lastly, GOP pollster Ogden & Fry found Biden up by 29 points over Sanders, and once we adjusted for house effects, Biden led by 27 points.

As for the overall state of the Democratic nomination race, not much seems in doubt at this point. Our forecast gives Biden better than a 99 in 100 shot of winning a majority of pledged delegates, leaving Sanders with less than a 1 in 100 chance. There’s also a less than 1 percent chance that no single candidate will capture a delegate majority, but that too is very unlikely at this point.

Besides the polls showing Biden well ahead in today’s contests, a couple of national polls conducted since last Tuesday reaffirm Biden’s sizable advantage in the Democratic race. Morning Consult’s survey from after the March 10 contests found Biden with a 21-point lead over Sanders, 58 percent to 37 percent. This marked a 3-point increase over Biden’s 18-point advantage that Morning Consult found the previous week. And a new NBC News/Wall Street Journal survey found Biden up by even more — 29 points. Biden led Sanders 61 percent to 32 percent, a sea change from the pollster’s last look at the race in mid-February, when Sanders led Biden 27 percent to 15 percent (with the then-crowded field making up the remainder). Neither of the margins in these two new polls shifted much after accounting for house effects either.

Taken together, the state and national surveys show a race that just isn’t all that competitive. Biden looks almost certain to win the nomination unless something wild happens. The question now is, just how much longer will the race go on? The results in today’s contests may help answer that and whether Sanders decides to fight on or to drop out of the race, making Biden the presumptive nominee.