Donald Trump's campaign is falling behind not just in the polls, but where some say it really counts in American politics -- fundraising.
In May, he raised only $3.1 million from donors -- well behind rival Hillary Clinton's $25.5 million (all figures in US dollars).
Adding a loan of $2.2 million from himself, he added $5.4 million to his election war chest.
So far Trump has taken in just $63.2 million in donations -- with about two-thirds of that a loan from the self-claimed billionaire himself, reports ABC News. Of that, he spent $6 million on his own companies and family.
Ms Clinton has taken in $232 million. At this point in the 2008 election campaign, Barack Obama had raised $287 million. In 2012, by the end of May Republican nominee Mitt Romney had $122 million.
If you count money raised by super PACS -- organisations outside of the official Republican and Democrat campaigns, but who campaign for one or the other -- Trump has $21.7 million left to spend, while Ms Clinton has $103.4 million.
Trump says it's because he's having "difficulty" with some high-ranking members of his party.
But he's not worried, saying if he has to he'll put in "unlimited cash" of his own.
His fundraising to date is the lowest of any major presidential candidate since the 2000 election, in which both Al Gore and George W Bush accepted public money, limiting the amount they were allowed to take from donors.
Trump's struggle to attract donations from people other than himself has sparked mockery on Twitter, under the hashtag #TrumpSoPoor.