Support for all three of the remaining Republican candidates has grown with the narrowing of the field, but Donald Trump still holds a double-digit lead over both his rivals for the GOP presidential nomination.

The latest Rasmussen Reports national telephone survey of Likely Republican Primary Voters finds Trump with 43% support to Senator Ted Cruz’s 28% and Ohio Governor John Kasich’s 21%. Just five percent (5%) of GOP voters like some other candidate, and three percent (3%) remain undecided. (To see survey question wording, click here.)

In our last survey of the Republican field just after the February 20 South Carolina Primary and Jeb Bush’s departure from the race, Florida Senator Marco Rubio and Dr. Ben Carson were still in the running. At that time, it was Trump 36%, Rubio 21%, Cruz 17%, Kasich 12% and Carson with eight percent (8%) GOP support.

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Despite Trump’s wins in most of the state primaries since then, all three of the candidates have experienced similar gains in support, but the billionaire businessman still holds a 15-point lead over his closest rival. Carson has endorsed Trump; the other candidates who have left the race over the past month have not thrown their support to anyone else at this point.

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Trump led the pack with 31% of the Republican vote in early February just before the New Hampshire primary and was ahead with 29% support in mid-December. He took the lead after the first debate in early August with 17% of the GOP vote.

Following his latest round of primary wins on Tuesday, more Republicans than ever believe Trump will be their party’s presidential nominee this fall.

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The national telephone survey of 719 Likely Republican Primary Voters was conducted by Rasmussen Reports on March 16-17, 2016. The margin of sampling error for the survey is +/- 4 percentage points with a 95% level of confidence. Fieldwork for all Rasmussen Reports surveys is conducted by Pulse Opinion Research, LLC. See methodology.

Democrats are getting closer to unifying behind Hillary Clinton’s candidacy, but the Republican elites opposed to Trump face some difficult questions if they still want to win the upcoming election.

The danger for Republicans is that 36% of the party’s voters say they are likely to vote for Trump if he runs as a third-party presidential candidate, with 24% who say they are Very Likely to do so.

Trump leads among both male and female Republicans.

Those 40 and over support Trump more strongly than younger voters do. Among voters under 40, he posts just a six-point lead over Cruz.

Among self-described conservative Republicans, it’s Trump 42%, Cruz 37% and Kasich 15%. Trump and Kasich are tied among moderates with Cruz far behind.

Most Republicans don’t consider Trump a conservative. A plurality (45%) regards him as a moderate instead. Conservative Republicans are among those balking the loudest at a Trump nomination.

Eighty-nine percent (89%) of Likely Democratic Voters think Clinton is likely to be their party’s presidential nominee in 2016. That includes 60% who say it is Very Likely, up 17 points from last month and the highest number of Democrats who consider Clinton’s nomination Very Likely in monthly surveys since last July.

Democrats are more excited about a Clinton-Trump race than Republicans are.

Seventy-two percent (72%) of Democrats blame Trump’s positions more than his opponents for the violence at some of his recent rallies. Just 39% of Republicans agree. Forty-five percent (45%) of Republicans blame his opponents instead.

Republicans and unaffiliated voters are more likely than Democrats to have changed candidates as a result of the presidential campaign debates.

Additional information from this survey and a full demographic breakdown are available to Platinum Members only.

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