Trump has ten point lead in latest YouGov national poll, Oct. 8-12, 2015 and is considered most likely to be Republican nominee by more than double nearest competitor-YouGov poll

.
Trump 28
Carson 18
Rubio 11
Fiorina 9
Cruz 8
Bush 7
Christie 3
Huckabee 3
Kasich 3
Paul 3
Graham 1
Jindal 1

Above, if election were today.

Oct. 8-12, 2015, 434 (p. 43) Registered voters who identified as Republican

10/14/15, "The Economist YouGov poll"

page 42, if election were today:

Trump 28
Carson 18
Rubio 11
Fiorina 9
Cruz 8
Bush 7
Christie 3
Huckabee 3
Kasich 3
Paul 3
Graham 1
Jindal 1
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YouGov sample:

Page 6, "3 point party ID" sample: 2,000 adults. 728 Democrat, 795 Independent, 477 Republican. 
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Who is most likely to be GOP nominee, asked of 476 Republicans, page 49:

Trump 34
Carson 14
Bush 13
Rubio 9

10/14/15, "What's happened to Jeb Bush?" Kathy Francovic, today.yougov.com

"Until two months ago, Bush was viewed as the most likely GOP nominee by Republicans. That is no longer the case: although Trump’s GOP support has dropped from his high point in the mid-30’s (28% name him as their first choice this week), he–not Bush--is viewed as the party’s most likely nominee. Just 13% say Bush is most likely to win the nomination."...

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p. 173
 
"Sampling method: Respondents were selected from YouGov’s opt-in Internet panel using sample matching. A random sample (stratified by age, gender, race, education, and region) was selected from the 2010 American Community Study. Voter registration was imputed from the November 2010 Current Population Survey Registration and Voting Supplement. Religion, political interest, minor party identification, and non-placement on an ideology scale, were imputed from the 2008 Pew Religion in American Life Survey."...


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