Where presidential projections models went wrong (and a little bit right)

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So what happened?

Tuesday morning, we reported that the eight presidential projection models that we had followed for more than a month had all identified Democrat Hillary Clinton as the leader, as they had since Oct. 3. Seven of the eight even gave her the 270 electoral votes needed for victory over now President-elect Donald Trump.

The holdout was RealClearPolitics. While it gave Clinton a sizable advantage (203 electoral votes to 164 for Trump), it shifted five states into the tossup category in the final week of the campaign: Pennsylvania, Michigan, Virginia, New Mexico and New Hampshire. Clinton ended up winning three of those states, but by capturing the two largest in that group, Pennsylvania and Michigan, Trump had closed another deal.

Once the final counts are in, Trump’s expected total will be 306 electoral votes to 232 for Clinton.

That doesn’t look like anything predicted by the projection models we tracked on the political website 270towin.com and RealClearPolitics. We should stress, however, that we frequently mentioned that these were projections based at least in part on polling, meaning they came with some margin of error. As former Washington Post political writer David Broder is credited with saying, “The only poll that matters is on Election Day.”

So here’s what each model projected and an explanation of where it was correct and where it went off the rails:

COOK POLITICAL REPORT FORECAST

Overall – Clinton 278 electoral votes to 214 for Trump

Up for grabs – 46 electoral votes

Florida (29), North Carolina (15), Maine (1) and Nebraska (1)

Likely voting for Clinton – 65 electoral votes

Pennsylvania (20), Michigan (16), Wisconsin (10), Colorado (9), Nevada (6) and New Hampshire (4)

Likely voting for Trump – 57 electoral votes

Ohio (18), Georgia (16), Arizona (11), Iowa (6) and Utah (6)

Good cooking: It did move North Carolina from likely voting for Clinton into the tossup category in the last week of the campaign, and the Tar Heel State provided some of the early drama on election night. Trump eventually won the state with 51 percent of the vote to 47 percent for Clinton.

In that last week, Cook also moved Arizona, Iowa and Ohio into the likely column for Trump.

What got burned: It listed Michigan, Pennsylvania and Wisconsin as likely voting for Clinton. When voters in those states sided with Trump, her firewall turned into ashes.

THE CRYSTAL BALL 2016 ELECTORAL COLLEGE RATINGS

The Crystal Ball is produced by Larry Sabato and his team at the University of Virginia Center for Politics.

Overall – Clinton 322 electoral votes to 216 for Trump

Up for grabs – zero

Leaning for Clinton – 90 electoral votes

Florida (29), Pennsylvania (20), Michigan (16), North Carolina (15), Nevada (6) and New Hampshire (4)

Leaning for Trump – 43

Ohio (18), Arizona (11), Iowa (6), Utah (6), Maine (1) and Nebraska (1)

What the Crystal Ball saw correctly: In the final week, it moved Arizona, Iowa, Ohio, Utah and the single congressional district votes for Maine and Nebraska into Trump’s likely column.

Where it could have used corrective lenses: It had Florida, Pennsylvania, Michigan and North Carolina all in the likely column for Clinton. If they had followed through, the president-elect would still just be known as “The Donald.”

FIVETHIRTYEIGHT POLLS-PLUS FORECAST

FiveThirtyEight combines polling data with information about the economy and voting histories. It defines a state as a tossup if no candidate has a better than 60 percent chance of winning the state.

Overall – Clinton 272 electoral votes to 215 for Trump

Up for grabs – 51 electoral votes (75 last week)

Florida (29), North Carolina (15), Nevada (6) and Maine (1)

Likely voting for Clinton – 33 electoral votes

Pennsylvania (20), Colorado (9) and New Hampshire (4)

Likely voting for Trump – 39 electoral votes

Ohio (18), Arizona (11), Iowa (6), Alaska (3) and Nebraska (1)

Where it got the numbers right: In the last week of the campaign, FiveThirtyEight shifted Iowa and Ohio to likely voting for Trump.

Where the math didn’t add up: It had Pennsylvania likely voting for Clinton. In its favor, the week before it had Pennsylvania as a safe state for Clinton.

THE FIX ELECTORAL COLLEGE RATINGS

The Fix is produced by the political team at The Washington Post.

Overall – Clinton 290 electoral votes to 209 for Trump

Up for grabs – 39 electoral votes

Florida (29), Utah (6) and New Hampshire (4)

Likely voting for Clinton – 105 electoral votes (109 last week)

Pennsylvania (20), Michigan (16), North Carolina (15), Virginia (13), Minnesota (10), Wisconsin (10), Colorado (9), Nevada (6), New Mexico (5) and Maine (1)

Likely voting for Trump – 113 electoral votes (84 last week)

Texas (38), Ohio (18), Georgia (16), Arizona (11), Indiana (11), Missouri (10), Iowa (6) and Alaska (3)

What doesn’t need fixing: In the final week, it moved Arizona and Ohio into the category of likely voting for Trump.

What’s in need of repairs: It had Michigan, North Carolina, Pennsylvania, Wisconsin and one of Maine’s congressional districts all down as likely voting for Clinton. They’re now the source of her broken dreams.

PREDICTWISE PRESIDENTIAL FORECAST

Overall – Clinton 322 electoral votes to 215 for Trump

Up for grabs – zero electoral votes

Defined as meaning no candidate has a 60 percent or higher chance of winning the state.

Leaning for Clinton – 44 electoral votes

Defined as meaning no candidate has more than a 79.9 percent chance of winning the state.

Florida (29) and North Carolina (15)

Leaning for Trump – 18 electoral votes (36 last week)

Ohio (18)

Prediction with precision: It moved Arizona, Iowa and one Nebraska congressional district into the safe column for Trump.

Time for a new Magic 8-ball: In the final week, it moved Florida from tossup to likely voting for Clinton, where it joined North Carolina. When that didn’t happen, the 8-ball went from “Without a doubt” to “Outlook not so good.”

REALCLEARPOLITICS

Overall – Clinton 203 electoral votes to 164 for Trump

Up for grabs – 171 electoral votes (111 last week)

Florida (29), Pennsylvania (20), Ohio (18), Georgia (16), Michigan (16), North Carolina (15), Virginia (13), Arizona (11), Colorado (9), Iowa (6), Nevada (6), New Mexico (5), New Hampshire (4) and Maine (3)

Leaning for Clinton – 35 electoral votes

Minnesota (10), Wisconsin (10), Connecticut (7), Oregon (7) and Maine (1)

Leaning for Trump – 9 electoral votes

South Carolina (9)

What was clearly real: In the final week, RCP shifted Michigan and Pennsylvania from likely voting for Clinton to tossup status. It probably helps if you declare 28 percent of the states as tossups.

What was clearly unreal: Wisconsin was listed as likely voting for Clinton. When the Badger State backed Trump, it caught many a television news anchor off-guard.

ROTHENBERG & GONZALES RATINGS

Overall – Clinton 323 electoral votes to 191 for Trump

Up for grabs – 24 electoral votes

Ohio (18) and Iowa (6)

Likely voting for Clinton – 100 electoral votes

Florida (29), Pennsylvania (20), Michigan (16), North Carolina (15), Wisconsin (10), Nevada (6) and New Hampshire (4)

Last week – Florida (29), Pennsylvania (20), North Carolina (15), Wisconsin (10), Nevada (6) and New Hampshire (4)

Likely voting for Trump – 44 electoral votes

Georgia (16), Arizona (11), Indiana (11) and Utah (6) (same as last week)

You can’t spell “right” without R & G: It listed Georgia, Arizona, Indiana and Utah as likely voting for Trump, which, frankly, was not that big a surprise. Besides that, it did move Michigan from safe for Clinton to likely voting for Clinton.

You can’t spell “wrong” without R & G: It had Florida, Michigan, North Carolina, Pennsylvania and Wisconsin as all likely to vote for Clinton.

UPSHOT PRESIDENTIAL FORECAST

The Upshot is produced by The New York Times, using polls, past election results and national polling.

Overall – Clinton 322 electoral votes to 198 for Trump

Up for grabs – 18 electoral votes

Defined as meaning no candidate has a 60 percent or higher chance of winning the state.

Ohio (18)

Leaning for Clinton – 54 electoral votes

Defined as meaning no candidate more than a 79.9 percent chance of winning the state.

Florida (29), North Carolina (15), Nevada (6) and New Hampshire (4)

Leaning for Trump – 30 electoral votes (34 last week)

Georgia (16), Iowa (6), Utah (6), Maine (1) and Nebraska (1)

What went up: In the last week it moved North Carolina from safe to leaning for Clinton, but that’s still wrong. It also moved Iowa and one of Nebraska’s congressional districts from tossup to leaning for Trump.

What got shot down: The listing of Florida and North Carolina in the leaning for Clinton category is obviously wrong. What you don’t see from what’s listed above is that Michigan, Pennsylvania and Wisconsin – which really broke Clinton’s back when they sided with Trump – were in her safe category, meaning The Upshot thought she had an 80 percent or better chance of winning each of them.

 

 

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