Donald Trump, a billionaire businessman and real estate developer, has moved to the top of a latest poll.

Trump garnered 15.8 percent of the vote of self-identified Republicans, compared to former Florida Gov. Jeb Bush's 16.1 percent, according to a new Reuters-Ipsos poll. While Trump has risen over the past two weeks, Bush has fallen. On June 30, Trump had 12.8 percent of support, while Bush had 16.9 percent.

The two were followed by New Jersey Gov. Chris Christie (9.5 percent), Kentucky Sen. Rand Paul (8.1 percent,) retired neurosurgeon Ben Carson (7.2 percent) and Wisconsin Gov. Scott Walker (5.8 percent.) These candidates were all within the margin of error of 5.7 percent.

Notably, 7 percent of people said they would not vote.

When given the choice of only three candidates — Trump, Bush or Florida Sen. Marco Rubio, who came in 11th place in this poll behind Huckabee, Perry and Cruz — Bush had a comfortable lead of 42 percent among Republicans. Roughly 30 percent chose Trump and 20 percent chose Rubio.

It is unexplained why pollsters chose this question, as in this poll Rubio only gathered 3.9 percent of the vote.

The poll of approximately 400 self-identified Republican voters was conducted July 6-10.