Trump expands lead to 53% nationwide, 31 points ahead of Republican field, Economist You Gov poll, March 10-12, 2016. Kasich tops with Democrat primary voters among GOP candidates. If Democrat voters could choose GOP nominee, it would be Kasich-YouGov

Trump 53
Cruz 22
Kasich 11
Rubio 10 
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Poll dates, March 10-12, 2016. Internet poll. Error margin, total pop. 2.9%. Not stated is number of likely Republican primary voters polled nor error margin of that subset.
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3/14/16, "Trump breaks 50% in national support for the first time," today.YouGov.com, Kathy Frankcovic

"Showing little sign of a "ceiling", Donald Trump has only grown in support with the exit of Ben Carson and Marco Rubio's collapse....

The week’s Economist/YouGov Poll finds Trump still at the top of GOP voters’ preference with a wider lead, while Florida Senator Marco Rubio seems most damaged by the two weeks of attacks and counter-attacks.

This is the first time Trump has garnered the support of a majority of Republican primary voters nationwide. YouGov's February 24-27 survey marked his previous high, at 44% support....

Rubio is the least liked of all the remaining GOP candidates.  His favorable rating among Republican primary voters has dropped nine points from what it was two weeks ago; his unfavorable rating has jumped eleven points in the same period.  Every other remaining contender, including Kasich, receives better ratings....

Kasich scores better with Democratic primary voters than any other GOP candidate (and if Democratic voters could choose the GOP nominee, Kasich would be the frontrunner).

Trump, who is the clear GOP frontrunner (74% of Republican primary voters expect him to be the nominee), still has a way to go to win over the supporters of his GOP opponents....

What separates Trump voters from those supporting other candidates is the importance of the issue of immigration.  While Republican voters generally think the economy is the country’s most important issue, no matter whether they are for or against Trump, Trump’s supporters are nearly five times as likely as supporters of other candidates to say immigration is the issue that matters most to them.  But Trump’s brashness may be more important than his issue positions. The most important reason people support Trump, chosen by both Trump supporters and opponents in the party, is that he is not politically correct."... 

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"Sampling Methodology"

page 24, Toplines: "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." From press release: "Full poll results can be
found here and topline results and margin of error here." 




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