(L-R) U.S. President George W. Bush listens to John Bolton speak after being appointed to be ambassador to the United Nations during an event at the White House August 1, 2005. (Mark Wilson/Getty Images)

Former U.N. Ambassador John Bolton wants certain donors to dig a little deeper into their pockets.

He sent an e-mail to a consultant and a staffer at his political action committee late afternoon Wednesday — that inadvertently appeared in the Loop’s inbox — asking them to check to see if a specific list of donors to his PAC in 2013 had also given in 2014.

“And any evaluation of whether they could give more — don’t need full call sheets unless you think it would be helpful,” Bolton wrote.

Among them? Fellow neoconservative and former Defense Secretary Donald Rumsfeld.

Rumsfeld and his wife Joyce gave a combined $10,000 to Bolton’s PAC in 2013. A quick look at FEC filings show that no, they have not donated again this year.

Bolton and Rumsfeld go way back to President George W. Bush’s administration where they were among the key architects of the Iraq War.

Bolton lists 11 donors in total in this rare peek behind the curtain at political fundraising efforts. For one, Joe Petrone, former U.S. Ambassador to the European Office of the United Nations during the Reagan administration, Bolton wrote, “could give considerably more, I think.” Petrone gave $1,000 in late 2013.

Bolton also wanted his advisers to call back Phil Rosen — most likely the same Rosen who bundled for Mitt Romney — and Michael Tuchin, a Los Angeles lawyer, because they both “had pledged but haven’t come through.”

For now, Bolton is using part of the money he raises to bolster Republicans candidates in tough races this cycle with a concentrated focus on bashing the Obama administration’s foreign policy.

But as our colleague Jaime Fuller wrote in July, Bolton has been a prolific fundraiser bringing in more than a million dollars to his John Bolton PAC — he also formed a super PAC last year — that raises speculation that he might be considering a presidential run in 2016.

As Fuller astutely wrote then, “few things are more important to a nascent presidential bid than a long e-mail list of people who have opened their pockets to you before.”