All of the Democratic presidential candidates have committed to rejecting the influence of special interests. To demonstrate their resolve, several of the candidates have promised to power their White House ambitions without a single dollar of lobbyist money. In the waves of small-dollar donations reported on Monday — the first financial disclosure reporting period of the 2020 presidential race — lobbyist money had made its way into the coffers of major candidates’ campaigns. Beto O’Rourke is one of the candidates who had pledge to run a campaign financed only by regular people — “not PACs, not lobbyists, not corporations, and not special interests.” His latest filing, however, shows that he accepted donations from a federal utility-company lobbyist and a top Chevron lobbyist in New Mexico.

Some lobbyist cash comes from individuals who are clearly lobbyists but have chosen not to register with a federal system rife with loopholes.

Sen. Kamala Harris, D-Calif., has also collected donations from registered corporate lobbyists in South Carolina, New York, and California. Several technology lobbyists from San Francisco have given to her campaign. Another Harris donor, Robert Crowe, from the firm, Nelson Mullins Riley & Scarborough, is a federal lobbyist who has worked to influence Congress on behalf of pipeline firm EQT Corporation and Alphabet, the parent company of Google. Sen. Cory Booker, D-N.J., similarly announced that he would eschew campaign donations from federal lobbyists, and his campaign appears to be making most of the caveat about “federal” lobbyists. Though he has returned donations from lobbyists registered under the federal government’s system, Booker has taken half a dozen donations from lobbyists registered under state and municipal lobbyist registration laws, but who do not appear in federal disclosures. The pledge to reject lobbyist cash is completely voluntary and self-defined. O’Rourke has made blanket statements that he will reject all donations from lobbyists. Harris has made promises in emails to her supporters to reject all lobbyist donations and, in other emails, to only reject donations from federal lobbyists. Booker’s campaign website only specifies that he will not accept money from federal lobbyists. The flow of lobby cash comes in many forms. Some comes from registered lobbyists, others from individuals who are clearly lobbyists but have chosen not to register with a federal system rife with loopholes. The Lobbying Disclosure Act, which governs the criteria over federal lobbyist registration, is notoriously easy to evade and historically poorly enforced. Many professional corporate influence peddlers — well-aware of the porous definitions set out in the statute — simply choose not to register. Take, for instance, Jay Carney, the former White House press secretary under President Barack Obama, who took a job as the vice president for worldwide corporate affairs at Amazon in 2015. Carney, the new campaign disclosures show, donated to Booker, O’Rourke, Harris, and South Bend, Indiana, Mayor Pete Buttigieg. The Carney donations, however, would not technically violate the lobbyist money ban, depending on how it is read, because he is not a registered lobbyist. The registration distinction makes little difference in the real world of professional public affairs. Amazon’s chief lobbyist reports to Carney, and Carney has been deeply involved in many of Amazon’s most high-profile efforts to sway public officials, including the bidding war over the company’s planned “HQ2″ expansion project. He also oversees Amazon’s lobbying office in Washington, D.C., which employs some 28 in-house lobbyists working on policy issues ranging from taxes to labor to artificial intelligence. Since Carney is not personally registered, does his donation count as lobbyist money? The donation disclosures released this week by the Federal Election Commission highlight a number of murky areas where candidates take special-interest cash despite pledges not to. John Buckley, chief executive officer of Subject Matter, a sprawling lobbying firm that represents corporate clients, such as health insurance giant UnitedHealth and oil giant BP, is an O’Rourke donor. Buckley, however, is not himself a registered lobbyist. Some donations clearly cross the threshold. The FEC disclosures show that O’Rourke also received money from Amy Thomas, a federal lobbyist for the American Public Power Association, as well as from Patrick Killen, a registered state lobbyist for Chevron in New Mexico.

The Harris campaign received the most registered lobbyist donations of any Democratic presidential campaign that has said it would not take the cash.

Booker appears to have closely followed his no federal lobbyist rule. The campaign revealed on Monday that it had returned a $1,000 from Kristen Ludecke, a federal lobbyist for PSEG, the largest utility company in New Jersey. But the Booker campaign continues to embrace corporate lobbyists that register under state and municipal registration guidelines. His campaign received campaign funds from multiple lobbyists working at Mercury Public Affairs; Dennis Marco, a local health care and pharmaceutical lobbyist; and from Dennis Culnan, a New Jersey lobbyist closely tied to the Norcross family political machine. The Harris campaign received the most registered lobbyist donations of any Democratic presidential campaign that has said it would not take the cash. The long list of state- and municipal-registered lobbyists giving to the Harris campaign includes Leecia Eve, a Verizon lobbyist in New York; Alex Tourk, an Airbnb lobbyist in San Francisco; Alexander Clemons, who represents AT&T; Cliff Berg, registered to lobby on behalf of Novartis, Cemex, and Visa; Darrell Campbell, a South Carolina lobbyist for Pfizer, Juul, HCA health care and Duke Energy; Emily Giske, a former Democratic National Committee superdelegate who lobbies for Cigna, IBM, and Google; Jennifer Wada, a charter school lobbyist; and Justin Ross, a Maryland construction and real estate lobbyist.