After a fiery first Republican Presidential Debate on August 6, the GOP primary field has continued to shift and change, leaving many pollsters struggling to catch up. To the surprise of many observers, Donald Trump has continued his surge – but new polling techniques helps clarify the nature of his support.

TAKE THE POLL: Who do independent voters support for president?

While most polls ask for second choices, few report the full breakdown of first and second choice support that allows more precise matching of candidates. In failing to do so, they give only a portion of the information needed to accurately understand the field as it may evolve in the coming months. Especially as candidates start to drop out, pollsters must ask voters to provide more information on their preferences and report that information with greater detail. Second-choice polls reveal what connections and crossovers exist among different groups of supporters.

As a start, polls can do something quite simple – and indeed something most polls are already doing in a limited manner. They should ask voters for their second-choice candidates and ideally their third-choice as well. With that additional data in hand, better analysis of it can provide a wealth of insight.

PPP Excels in Presentation of Second Choices

As we recently blogged, Public Policy Polling (PPP) continues to show leadership in their collection and presentation of second choice data. Not only does the firm present the aggregate second-choice percentages, PPP reports the full breakdown of who each candidate’s supporters would select as their second choice.

Take PPP’s August 25 poll on New Hampshire. Part of its finding was that businessman Donald Trump is dominating the field – he is at 35% in New Hampshire, with John Kasich far back at 11%, followed by Carly Fiorina with 10% and Jeb Bush and Scott Walker tied with 7%. Trump finishes third among respondents for second-choice votes with 8% – only slightly behind Ben Carson (11%), and Carly Fiorina (10%). In other words, Trump is either the first- or second-choice of 43% of respondents, while former front-runner Jeb Bush is the first- or second-choice of only 14%.

PPP presents its second-choice polling data in a simple one-page table form that provides a more detailed picture of the field than polls only asking for first choices or only reporting aggregate first- and second-choice data. For example, these results tell us that not only is Carly Fiorina one of the more popular first-choice and second-choice candidates, but she has broad appeal among other candidates’ supporters -- with sizable percentage of the second-choice support from Ben Carson, Chris Christie, Rand Paul, Marco Rubio and Scott Walker. If Fiorina keeps rising and any of these candidates falter or drop out, she stands to gain.

The real emerging winner of these second-choice results, however, is Donald Trump. Over the past few months, expectations of Donald Trump’s impending implosion have been almost as persistent as his rise in popularity. Political commentators and candidates alike have repeatedly predicted his departure from the race, insisting that his following among the Republican electorate is deep but narrow. That may have been true earlier in the summer, but the new numbers from PPP show a more complex story: a candidate who is starting to draw support from both establishment and anti-establishment voters in New Hampshire, but is far more polarizing in North Carolina.

Trump’s Impressive Breadth of Support

In New Hampshire, Trump is the leading second-choice option among the supporters of almost every establishment candidate including Jeb Bush and John Kasich. Trump earns the second-choices of 19% of Jeb Bush supporters, easily beating more moderate candidates like Kasich (9%), Walker (6%), and Rubio (1%). This trend continues among John Kasich supporters, 16% of whom would chose Trump second, ahead of all the other candidates.

Among other establishment candidates, Trump only narrowly trails Jeb Bush as the most popular second choice. Twenty-four percent (24%) of Rubio supporters listed Jeb Bush as their second-choice, compared to the 22% who listed Trump as their second-choice. Trump also earns a sizable 20% second-choice support from Scott Walker, just 1% behind Marco Rubio and Fiorina.

Interestingly, the reverse of this trend does not hold true. Trump’s large number of first-choice supporters show notably little interest in selecting establishment candidates as their second choice. Instead, fellow outsider candidate Ben Carson emerges as the most popular second-choice for Trump supporters, with similar outsider candidates Ted Cruz and Carly Fiorina trailing close behind him. Trump’s supporters remain as pleased as ever with their varied outsider second-choice options – and if his campaign indeed does fade, the establishment candidates may not gain.

So, with data limited to just first- and second-choice numbers, one-on-one comparisons make Trump’s lead all the stronger. Here are a few examples:

Contrast with New Hampshire: Trump May Hit Ceiling

PPP on August 19 released another state poll from North Carolina. Here again, Trump leads in first-choices with 24%, ahead of Carson (14%), Bush (13%) and Cruz (10%). But his second-choice support is far smaller – he is the second-choice of only 2% of backers of the other candidates, trailing eight other candidates and far behind Ben Carson (21%), Bush (13%), and Fiorina (12%). Note the same one-on-one comparisons here.

In short, while Trump clearly has a hold on the anti-establishment vote and is building new support from backers of establishment candidates in New Hampshire, he is facing a very different scenario right now in a more socially conservative state. He certainly could win a plurality in such a state, but right now would likely lose one-on-one to several other candidates. That’s not to say that if primaries were held next week that he couldn’t win the nomination – Mitt Romney lost his share of primaries in 2012, for example—but his success will depend on building the kind of depth of support he is showing in New Hampshire.

More Information with Second-Choices, Well Presented

Capturing and showing this more specific second-choice data reveals the true breadth of Trump’s support beyond his first-choice base. When pollsters take advantage of this method, the data offers a timely and unique ability to estimate which candidates will rise and fall as the primary season continues and the field inevitably narrows. Trump’s substantial second-choice support among a wide range of establishment and anti-establishment candidates could foreshadow a growth rather than a reduction in his popularity throughout the fall.

Polls that don’t ask participants for their second-choices or only show aggregate data are limited to an incomplete picture of a dynamic and shifting Republican primary field. To really understand how the field will adjust to drop outs, and which candidates have sturdy support, we must start asking voters to rank the field. We hope PPP’s leadership will inspire other polling firms to expand their reporting practices, and contribute to a more accurate and more reflective understanding of voter support.

FairVote is seeking to make this easier for pollsters. Working with Civinomics, we have developed an innovative ranked choice voting app that, in its beta form, allows users to rank candidates in the Republican field. Then, in showing the results, users can manually eliminate candidates to see where their second support goes, or run a ranked choice voting tally to see who would win under that system designed to test the two strongest candidates one on one. We soon will be able to import pollsters’ ranked choice data into the app, so that it can be analyzed more fully. Stay tuned!

Editor's note: This article, written by Rob Richie and Molly Rockett, originally published on FairVote's blog on September 1, 2015, and has been slightly modified for publication on IVN. To learn more about FairVote, visit the organization’s website or follow the group on Facebook or Twitter.