# Which polls will be off by how much 3/15? **URL:** \ **Category:** Politics & Elections\ **Created:** [March 10, 2016, 3:47pm UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549 "2016-03-10T15:47:32Z")\ **Posts on this page:** 13\ **Page:** 1
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [March 10, 2016, 3:47pm UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/1 "2016-03-10T15:47:32Z")
Michigan’s epic polling fail raises the specter that polls this year can be off and off big. The following are the current Tuesday’s RCP rolling poll averages (subject to change with more data). NC Clinton +20.2 FL Clinton +31.5 IL Clinton +30.5 MO Only very old data. OH Clinton +20 In each case the peaks for 538’s “polling plus” method give Clinton bigger leads. How will polling do this time? Personally I am guessing that Florida, being a closed primary, will be pretty spot on. But the others will be smaller than poll prediction Clinton wins, not on the Michigan scale however. ---
**Author:** ![Nonsuch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nonsuch/32/2922_2.png) [@Nonsuch](https://boards.straightdope.com/u/Nonsuch)\ **Post date:** [March 10, 2016, 4:14pm UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/2 "2016-03-10T16:14:17Z")
I’m guessing we’ll see a lot of pollsters rejigger their models to account for a higher turnout of young voters, so I’d expect to see Clinton’s margins of victory narrowing, if only a little. ---
**Author:** ![Lance\_Turbo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lance_turbo/32/6156_2.png) [@Lance\_Turbo](https://boards.straightdope.com/u/Lance_Turbo)\ **Post date:** [March 10, 2016, 4:45pm UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/3 "2016-03-10T16:45:59Z")
There’s a [preliminary autopsy](http://fivethirtyeight.com/features/why-the-polls-missed-bernie-sanders-michigan-upset/) at 538 that tryies to explain what may have happened. The main point is that multiple things went wrong and any on of the following factors would not have been enough on its own to explain what happened. [ul] [li]Pollsters underestimated youth turnout. [/li][li]Pollsters underestimated Sanders’s dominance among young voters.[/li][li]Pollsters underestimated the number of independent voters who would participate in the primary.[/li][li]Pollsters underestimated Sanders’s support among black voters.[/li][li]Pollsters missed a late break to Sanders by not polling after Sunday.[/li][li]Some Clinton supporters chose to vote in the Republican primary.[/li][li]Pollsters had little recent history to work with.[/li][li]This is an outlier, a perfectly rotten combination of bad luck and bad timing.[/li][/ul] Many of those are correctable by the pollsters and at least one is unique to Michigan. I suspect that most polls we see between today and 3/15 will have made some adjustments and some will have over-corrected. All in all I think the polling averages will shift a noticeable amount in the next week, but the polling averages on 3/15 will on average give us a pretty good idea of what to expect. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [March 10, 2016, 4:59pm UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/4 "2016-03-10T16:59:16Z")
I do wonder how much the MI mega-fail had to do with Michigan specific items. They have not had a well attended recognized primary Democratic primary in a while (given that 2012 was uncontested and in 2008 they had that whole going early against the rules and only Clinton actually running there bit) … maybe their likely voter lists and screens were impacted? Or maybe the means by which Team Clinton does outreach were? ---
**Author:** ![Lance\_Turbo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lance_turbo/32/6156_2.png) [@Lance\_Turbo](https://boards.straightdope.com/u/Lance_Turbo)\ **Post date:** [March 10, 2016, 5:23pm UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/5 "2016-03-10T17:23:57Z")
This one is interesting to me. [ul] [li]Some Clinton supporters chose to vote in the Republican primary.[/li][/ul] I’m pretty sure it’s minor in the grand scheme of things, but there’s no way to know for sure. The reason why it caught my eye is that there is poster here who is a Clinton supporter and not only says that he’ll crossover vote for Trump but also has a [thread](http://boards.straightdope.com/sdmb/showthread.php?t=785322)advocating that others do the same. I also believe this poster is voting in Missouri on 3/15. ---
**Author:** ![AHunter3](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ahunter3/32/368_2.png) [@AHunter3](https://boards.straightdope.com/u/AHunter3)\ **Post date:** [March 10, 2016, 5:34pm UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/6 "2016-03-10T17:34:02Z")
[electoral-vote.com](http://electoral-vote.com) also has a [portmortem](http://www.electoral-vote.com/evp2016/Pres/Maps/Mar10.html#item-8) in which they blame the screen for “likely voters” ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [March 11, 2016, 10:16pm UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/7 "2016-03-11T22:16:28Z")
Updating. So far at least the polls are not narrowing as pollsters rejigger. Florida and Illinois polling averages are both moving towards bigger Clinton wins; Ohio no new data. NC marginally more to Clinton. I will still be surprised if they are not a wee bit underestimating how Sanders will do; I am expecting more modest Clinton wins in these states. But how likely do you think [this](http://www.nytimes.com/2016/03/12/us/politics/bernie-sanders.html?hpw&rref=politics&action=click&pgtype=Homepage&module=well-region®ion=bottom-well&WT.nav=bottom-well) result is? > [@](#): > > Several Democratic strategists and pollsters said they now thought Mr. Sanders could win the Ohio primary — and perhaps Illinois and Missouri — after the senator performed unexpectedly well among independents and young people in Michigan and also beat Mrs. Clinton by more than 10 percentage points with white voters there, according to exit polls. Mr. Sanders also won support from about 30 percent of Michigan’s black voters, a larger share than in recent contests in the South, a sign that he might be able to stop Mrs. Clinton from winning the landslides she is aiming for in predominantly black neighborhoods in Chicago, Cleveland and St. Louis. > > “After Michigan, Bernie can certainly win Ohio, and frankly you cannot write him off in any major urban metropolitan state anymore,” said Peter D. Hart, a veteran Democratic pollster. … > > … “If Sanders wins Ohio, there is a new narrative for the next three months and the nomination fight goes on to the California primary on June 7 in a way that no one ever predicted,” said Robert Shrum, a veteran political adviser to several Democratic presidential campaigns. … For this thread the subject is not the tactic of downplaying delegates and raising the importance of how many states won and selectively naming particular ones as the ones that matter (Virginia and Florida … not important at all). Just if that statement “After Michigan …” is a reality based in any way. ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [March 12, 2016, 3:51am UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/8 "2016-03-12T03:51:16Z")
Hey finally [a Missouri poll](http://www.realclearpolitics.com/epolls/2016/president/mo/missouri_democratic_presidential_primary-5606.html)! Only 145 LV and who knows what cred the polling house has. FWIW though Clinton +7 with a MOE of 8. ---
**Author:** ![Martin\_Hyde](https://avatars.discourse-cdn.com/v4/letter/m/47e85d/32.png) [@Martin\_Hyde](https://boards.straightdope.com/u/Martin_Hyde)\ **Post date:** [March 12, 2016, 5:02am UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/9 "2016-03-12T05:02:45Z")
I believe at least Illinois and Ohio have had early voting going on which I think throws wrenches in the polling models as well. ---
**Author:** ![adaher](https://avatars.discourse-cdn.com/v4/letter/a/dec6dc/32.png) [@adaher](https://boards.straightdope.com/u/adaher)\ **Post date:** [March 13, 2016, 2:33am UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/10 "2016-03-13T02:33:28Z")
Primary polls always have a large margin of error. Michigan is one of the largest we’ve ever seen, but 10 points off is not at all unusual. Trump has pretty consistently underperformed everywhere but the South, and Sanders has pretty consistently overperformed except in the South. ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [March 13, 2016, 2:43am UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/11 "2016-03-13T02:43:28Z")
> [@DSeid](#): > > Hey finally [a Missouri poll](http://www.realclearpolitics.com/epolls/2016/president/mo/missouri_democratic_presidential_primary-5606.html)! Only 145 LV and who knows what cred the polling house has. FWIW though Clinton +7 with a MOE of 8. [Fivethirtyeigtht.com](http://Fivethirtyeigtht.com) gives the weighting in [their polling algorithm](http://projects.fivethirtyeight.com/election-2016/primary-forecast/missouri-democratic/). They give it around a .22 compared to [another recent poll](http://www.rabaresearch.com/) which has a .77. Though what specific factors affect those numbers is left unstated. (The second link goes to the polling site’s front page, which, as of this post, has a press release announcing the results of the poll. I was unable to find a direct link to the press release or to a graphic showing the poll.) ---
**Author:** ![DSeid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dseid/32/20194_2.png) [@DSeid](https://boards.straightdope.com/u/DSeid)\ **Post date:** [March 13, 2016, 5:33pm UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/12 "2016-03-13T17:33:25Z")
Thank you for that. Meanwhile at least one [polling house](http://www.cbsnews.com/news/election-2016-trump-and-kasich-neck-and-neck-ohio-trump-leads-florida/) is breaking from the pack and showing a narrowed Sanders deficit in Ohio and a LEAD in Illinois! Florida though not much different. Ohio Clinton +9 Illinois Sanders +2 Florida Clinton +28 On the Illinois side [another pollster](http://www.nbcnews.com/meet-the-press/polls-trump-ahead-florida-illinois-kasich-leads-ohio-n537356) has also shown it narrowing, albeit still a Clinton lead: down to Clinton +6. For Ohio and Florida though they are with the rest of the pack. Again for this thread the interest is why the divergence between pollsters and if any will capture reality. Was Michigan a one-off polling epic fail or are the pollsters structually missing something more broadly? ---
**Author:** ![CarnalK](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnalk/32/486_2.png) [@CarnalK](https://boards.straightdope.com/u/CarnalK)\ **Post date:** [March 13, 2016, 5:41pm UTC](https://boards.straightdope.com/t/which-polls-will-be-off-by-how-much-3-15/748549/13 "2016-03-13T17:41:28Z")
Well as far as why the divergence, I think it’s common knowledge that the poll industry is in a bit of flux right now. They are still trying to learn how to deal with decreased participation, the ongoing death of landlines and how to do a useful internet survey.