Roy Blunt, who voted against limiting the US’s role in the Yemen war, received $19,200 from pro-Saudi lobbyists in 2017.

At least five of the 37 Republican Senators who voted against advancing a resolution limiting the United States’ involvement in the war in Yemen have received campaign contributions from pro-Saudi lobbying groups.

Roy Blunt, John Boozman, Richard Burr, Mike Crapo and Tim Scott all received financial contributions from firms representing Saudi interests between 2016 and 2017, according to a recent investigation by the Centre for International Policy (CIP).

All five Republicans voted on Wednesday against advancing the resolution, which, if passed, would force the US to limit its support for the Saudi-UAE war in Yemen.

Blunt, one of the two Senators from Missouri, received at least $19,200 in campaign contributions from firms representing Saudi Arabia in 2017, the CIP said, with Boozman, Burr, Crapo and Scott, representing Arkansas, North Carolina, Idaho and South Carolina respectively, receiving contributions ranging from $1,000-$2,500 between 2016 and 2017.

Al Jazeera reached out to the Senators but none of them responded to our requests for comment.

Last year, the oil-rich kingdom spent at least $24m to influence US policy and public opinion, according to disclosures to the Department of Justice made available through the Center for Responsive Politics’ Foreign Lobby Watch tool.

Around $18m of that was paid to foreign agents acting on behalf of Saudi interests in 2017 and another $6m in spending has already been reported this year.

According to the CIP, it made Saudi Arabia one of the top 10 countries spending on influence and lobbying in the US.

But on Wednesday, the political donations appeared to have little effect when the US Senate opted to move forward with the resolution in a bipartisan 63-37 vote.

I changed my mind because I'm pissed. The way the administration has handled Saudi Arabia is not acceptable Lindsey Graham, Republican Senator

It’s time to send Saudi Arabia a message

Delivering a massive blow to the Trump administration, Republican Senator Lindsey Graham said he flipped sides because of the way the government had handled the murder of journalist Jamal Khashoggi.

“I changed my mind because I’m pissed,” Graham said following the vote.

“The way the administration has handled Saudi Arabia is not acceptable.”

Khashoggi, a US resident and Washington Post columnist, entered the Saudi consulate in Istanbul on October 2 to obtain documents certifying he had divorced his wife so he could remarry.

After weeks of repeated denials that it had anything to do with his disappearance, Riyadh eventually acknowledged that its officials were behind his murder.

In October, Graham had said he felt “completely betrayed” by the Saudis.

Senators on both sides of the political divide, many of whom have historically backed the US-Saudi relationship, have vented their anger over the killing and have pulled their support for the war in Yemen in an attempt to communicate their displeasure.

The Saudis, lobbyists, the Secretary of Defense, none of them have been able to stop this anger which is brewing Akbar Shahid Ahmed, Huffington Post

‘Despotic, dishonest dictatorship’

Democratic Senator Bob Menendez, who had also previously opposed the Yemen resolution, said it was “time to send Saudi Arabia a message both on its violation of human rights and the incredible humanitarian catastrophe it’s creating”.

Yemen has been torn apart by conflict since 2014, when Houthi rebels, allied with troops loyal to former President Ali Abdullah Saleh, captured large expanses of the country, including the capital Sanaa.

Saudi Arabia launched a massive aerial campaign against the rebels in March 2015, aimed at restoring the government of exiled President Abd-Rabbu Mansour Hadi.

Since then, the US has been helping the Saudi-UAE military alliance with weaponry and logistical support. Until recently, it was also refuelling the alliance’s planes which were responsible for the more than 18,000 raids carried out on the war-ravaged country.

More than three-quarters of the population – some 22 million people – need humanitarian assistance, while 11 million require dire help in order to survive.

Senator Bernie Sanders, who co-sponsored the bill, said the time to end the US involvement in the war was now.

“We have already seen 85,000 children starved to death, the UN tells us that millions of people are facing starvation, 10,000 new cholera cases are developing each week because there is no clean drinking water in the country,” Sanders said following the briefing.

“All of that was caused by the Saudi-led invasion of Yemen three years ago, led by a despotic, dishonest dictatorship.”

Mounting calls to end the war

The bipartisan bill intends to exploit a powerful but rarely activated provision in a 1973 law – the War Powers Act – that gives Congress the authority to overrule the president and withdraw troops if the former believes the conflict is not authorised.

Shireen Al-Adeimi, a Yemeni political analyst and assistant professor at Michigan State University, said while it was “shameful” Senators were receiving campaign donations from pro-Saudi groups, anti-war activists were hopeful the resolution had advanced and could help end the war.

“This was just the first hurdle,” she said.

“Now that we have permission to debate this issue, we expect a prolonged debate, over ten hours or more, which will be followed by a very long vote.

“Given all the setbacks this bill has faced in the past, we are hopeful that we can finally discuss it and vote upon it.

The Trump administration, however, has threatened to veto the resolution if it passes.

Brett Bruen, a former director of Global Engagement in the White House under President Barack Obama, said it appeared Senators on both sides were not won over by the Trump administrations claims.

“It’s a major rebuke of the Trump administration and of Secretary Pompeo in particular, who this morning made his case about why the US support for the Saudi operations in Yemen were so critical,” he told Al Jazeera.

“Clearly Senators were not convinced.

“What we’re seeing are several issue play out. The Trump administration for the first part of the term has been able to ride roughshod over congressional oversight.

“What we’re seeing now is both Democrats and Republicans saying: ‘We want to look at these issues. We want to look at the direction that you’re heading on whether it’s on Saudi Arabia, Iran or North Korea’.

Pressure has been mounting for the US to end its support for the conflict. According to a recent YouGov poll, 89 percent of liberals Americans and 54 percent of conservatives expressed an opinion opposing continued arms sales to the Saudi-UAE alliance fighting in Yemen.

Akbar Shahid Ahmed, a foreign affairs reporter with the Huffington Post, called Wednesday’s vote “unprecedented.”

“What this shows is that President Donald Trump hasn’t been able to keep his own party, and his allies like Senator Graham and Senator Corker in line,” he told Al Jazeera.

“The Saudis, lobbyists, the Secretary of Defense, none of them have been able to stop this anger which is brewing.

“Over the last three years we’ve seen the Senate get closer and closer [in pushing for a halt] to the sale of bombs, tanks etc to Saudi Arabia, but the Saudis have just continued in Yemen.

“They haven’t stopped. They keep saying: Iran, Iran, Iran. But that isn’t enough for Capitol Hill anymore.”

Follow Al Jazeera’s Faisal Edroos on Twitter: @FaisalEdroos