Aug. 19-Sept. 1, 2015. Trump #1 in favorability among Republicans with 63 per Gallup:
9/4/15, "Trump's Image Up Sharply Among Republicans," Gallup, Frank Newport
(Scroll down, this chart last on page)
Despite some political analysts' expectations that Trump's bombastic
style and controversial statements could begin to weaken his standing
among Republicans, the businessman and TV personality's net favorable
score has actually jumped over the past two weeks, and he is now in a
much stronger position image-wise than in mid-July. From a broad
perspective, these data show no signs yet of an overall backlash among
rank-and-file Republicans to his campaign, style or issue positions."...
"Results for this Gallup poll are based on telephone interviews
conducted July 8-Sept. 1, 2015, on the Gallup U.S. Daily survey, with a
random sample of 13,996 Republicans and Republican-leaning independents,
aged 18 and older, living in all 50 U.S. states and the District of
Columbia. Each candidate was rated by a random subset of respondents
during this period, with the sample sizes rating each candidate
averaging about 1,000 Republicans and Republican-leaning independents
within each two-week interviewing period.
For results based on the total sample of Republicans and
Republican-leaning independents, aged 18 and older, rating each
candidate at each time period, the margin of sampling error is ±4
percentage points at the 95% confidence level. All reported margins of
sampling error include computed design effects for weighting.
Each sample of national adults includes a minimum quota of 50%
cellphone respondents and 50% landline respondents, with additional
minimum quotas by time zone within region. Landline and cellular
telephone numbers are selected using random-digit-dial methods."...