WASHINGTON, Aug. 2 (UPI) -- The polling bumps enjoyed by both Donald Trump and Hillary Clinton in the days following their party conventions appeared in tandem with a significant drop in voters who had previously declined to state a preference for either candidate, according to UPI/CVoter polling data released Tuesday.
"Other" voters -- defined in the poll as any respondent who declined to pick either Trump or Clinton -- represented a 14.1 percent share of the electorate on July 17, the eve of the Republican National Convention. Five days later, after the GOP convention had wrapped up, that share had steadily dropped to 8 percent, while Trump's percentage of the vote rose from 39.4 percent to 48.2 percent.
A week later, Clinton's Democratic National Convention appeared to have a similar effect, albeit without as dramatic a shift given Trump had claimed a large share of the "other" voters available headed into the conventions. Clinton opened the DNC with "others" clocking in at 6.4 percent. Five days later, after that convention ended, "others" were at 4.9 percent, where they have remained since.
Clinton's percentage of the vote in the poll rose steadily through both conventions, beginning the GOP affair at 45.2 percent and ending after the DNC at 47.3 percent.
While Trump appears to have benefited more from his convention bounce – going from 39 percent to 48 percent – that is also partly a reflection of his standing as the prohibitive underdog headed into the back-to-back conventions.
Clinton, on the other had, may have won over some of the "others" who initially sided with Trump. Her post-convention bounce correlated with a slight decrease in both the "others" and Trump's percentage of the vote, which has declined slightly but steadily since his convention ended and the Democrats took the spotlight.
The full effect of the feud between Trump and the parents of a Muslim soldier killed in Iraq who spoke Thursday during the closing night of the Democratic convention has not been felt in the poll, however Trump had ticked down slightly by Tuesday, while Clinton had risen slightly over the same time frame.
The issue might not have yielded a swing toward Clinton, but it shows a slight downturn for Trump. As the controversy is still continuing, the impact could become more visible over this week when post-convention data gets more representation in the seven-day day rollover sample.
Trump's post-convention high was recorded July 24, the night before the Democratic National Convention began. It has steadily decreased since then, going from 49.2 percent to 46.3 percent on Monday.
As Trump's numbers slid backward, Clinton edged up, from 44 percent on the eve of her convention to 49 percent on Sunday, her high-water mark over that time frame.
The results were calculated based on online polling conducted from July 26 to Aug. 1. Because UPI and CVoter rely on online polling where users self-select to participate, a margin of error cannot be calculated. The poll surveyed 1,328 individuals, including 1,006 self-described likely voters over that time frame. The poll's credibility interval is 3 percentage points.