WASHINGTON, Aug. 25 (UPI) -- The UPI/CVoter daily presidential tracking poll released Thursday shows Republican Donald Trump pulling into a slight lead over Hillary Clinton for the first time in nearly a month.

The online poll shows Trump with 48.29 percent to Clinton's 47.59. The two have been in a virtual tie in the poll for several days, though Thursday's data is the first to show Trump in the lead.


The most recent data show a small but measurable change for both candidates: a 0.8 percentage point increase for Trump and a 0.7 decrease for Clinton.

Thursday's data is the first time Trump has held a lead in the race since before the Democratic National Convention, after which Clinton received a substantial bounce and Trump backslid amid the controversy surrounding his criticism of a Gold Star military family.

Thursday's data is also the first to incorporate voter feedback in the wake of an Associated Press article detailing Clinton's close ties with big donors to the Clinton Foundation while she was secretary of state. The full effect of that news will not be measured for about a week, as older data is pushed out by new responses.

The UPI/CVoter online tracking poll surveys at least 200 people each day, leading to a sample size of more than 1,400 people during any seven-day span.

Because the poll is conducted online and individuals self-select to participate, a margin of error cannot be calculated. The poll has a credibility interval of 3 percentage points. This seven-day span includes data collected from Aug 17-23, when 1,737 individuals were surveyed. Of them, 1,196 identified themselves as likely voters.

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