Republican presidential candidate Donald Trump narrowed his deficit to Democratic rival Hillary Clinton to 7 percentage points from 15 points late last week, a Reuters/Ipsos poll released on Tuesday finds.

The poll took place as delegates at the Republican National Convention in Cleveland officially nominated Trump as the party’s candidate for the November 8 presidential election.

43 percent of likely voters supported Clinton in the July 15-19 poll, while 36 percent supported Trump. The poll included 1,069 voters and had a credibility interval, a measure of accuracy, of 3 percentage points.

The previous poll, in which Trump trailed Clinton by 15 percentage points, covered the five-day period that ended July 14.

A previous poll released the first week of July found that Clinton had a lead of 13 percentage points over Trump.

Trump’s rise appeared partly fueled by a decline in the number of voters who remained on the sidelines. The percentage of voters who supported neither candidate dropped to 12 percent in the July 15-19 poll from 15 percent in the July 10-14 poll.

Despite the fact that Clinton has maintained a lead over Trump in most polls, Tuesday’s poll is another indication of a recent trend that shows that the billionaire has been chipping at that lead.