This brutal stat shows one reason Rick Perry's campaign is on the verge of collapse

The presidential campaign of former Texas Gov. Rick Perry (R) is running on fumes. And one reason may be that an upstart rival is taking many of his former donors.

Perry's campaign reportedly stopped paying staffers following last Thursday's first Republican presidential debates. And as Perry has struggled to raise cash, one of his rivals, Sen. Ted Cruz (R-Texas), has raked in large sums from past Perry supporters.

According to an analysis published by the National Journal on Friday, Cruz has raised more than $895,000 this year from people who supported Perry's 2012 presidential campaign. Perry has raised less than half that amount, $376,000, from his former supporters.

Overall, National Journal reported Perry has raised a little more than $1.1 million in the first half of this year. Cruz has raised nearly that amount just from Perry's old supporters during the same period.

Perry's campaign did not respond to a request for comment on this story. However, Business Insider recently overheard Perry's campaign manager, Jeff Miller, discussing fundraising strategy with another reporter. The conversation took place after Perry's speech in New York on July 29, a little more than a week before the GOP debates.

Miller was asked how fundraising was going for the campaign. He said it was just "OK," but added the campaign expected donations would pick up after people saw Perry perform in the main Republican debate. Perry ended not qualifying for the main debate, which featured the top 10 candidates in a recent selection of national polls. Instead, he participated in a lower-profile debate that included the seven GOP hopefuls who are behind in the polls.