In the wake of the brutal murder of Jamal Khashoggi, the Senate voted last week to advance a resolution ending U.S. involvement in the Saudi-led coalition’s war in Yemen. We are now awaiting a Senate floor debate and a motion to proceed, which could come as early as Monday.

While the measure passed, opposition from the Saudi lobby was fierce and strongly reflected in the vote. In fact, of the 37 senators who voted against the measure, 30 have received campaign contributions from lobbying firms working for the Saudis. In total, an analysis of Foreign Agents Registration Act (FARA) records reveals at least $226,182 in campaign contributions reported by firms registered to represent Saudi Arabia that went to these 30 senators over the past two years.

The top recipient of Saudi lobbying firm contributions among senators who voted against the measure was Dean Heller, Republican of Nevada, who received $27,150. Heller’s vote against the resolution on Wednesday was notable given that he had previously voted against an arms sale to Saudi Arabia and was a co-sponsor of legislation that would have prohibited the U.S. military from refueling Saudi warplanes.

Heller’s haul from Saudi lobbyists was closely followed by Roger Wicker, Ted Cruz, and Roy Blunt, Republicans all, who have received $25,550, $23,000, and $19,250, respectively, from Saudi lobbyists over the past two years. On the campaign trail, Cruz called the possibility of the Saudi government ordering the murder of Jamal Khashoggi “troubling” and said “there should be real consequences for that.” His vote Wednesday was to block one of those consequences.

Blunt, unlike Cruz, has been largely uncritical of the Saudis’ role in Khashoggi’s death. Recently, he rejected the Central Intelligence Agency’s reportedly “high confidence” assessment that Saudi Crown Prince Mohammed bin Salman had ordered the killing of Khashoggi, saying, “we don’t quite have all the information we’d like to have.”

Several of the senators who voted against the resolution received contributions from lobbyists on the same day they or their offices were contacted on behalf of the Saudis: Mike Crapo, John Boozman, Richard Burr, and Tim Scott.

To be sure, lobbyists and firms working for the Saudis have also made considerable campaign contributions to senators who voted for the measure. For example, Bob Corker, who voted for the resolution, has been one of the most outspoken critics of the Saudis following Khashoggi’s murder and recently called the crown prince “out of control.” Yet a Hogan Lovells FARA filing shows that the firm’s Saudi lobbyists met with Corker on April 26, 2017, and a lobbyist at the firm made a $2,700 contribution to Corker’s campaign that same day. Two months later, Corker’s campaign also received a $1,350 contribution from a Hogan Lovells lobbyist.

In addition to Corker, Democratic Senators Tim Kaine and Bill Nelson have been extremely critical of the Saudis and voted for the resolution to end U.S. support for the war in Yemen. This was despite Kaine being the top recipient of contributions from Saudi lobbyists, at $41,650, and Nelson being second, at $29,050, according to FARA filings from 2017 and 2018.

Corker, Kaine, and Nelson show that campaign donations don’t necessarily determine votes. But the 37 senators that voted against punishing Saudi Arabia even after learning that the CIA concluded that the Saudi crown prince ordered Jamal Khashoggi’s murder shows that the Saudi lobby’s influence nonetheless remains strong. Campaign contributions have been, and will continue to be, a key weapon for the Saudis in trying to keep members of Congress in line.

Ben Freeman is the director of the Foreign Influence Transparency Initiative at the Center for International Policy and author of the The Foreign Policy Auction, an investigation of foreign influence in America.