(CNN) -- Cambridge Analytica, the data company Donald Trump's campaign hired during the 2016 presidential election, has been under a magnifying glass this week after a whistleblower claimed that the firm misused the personal data of about 50 million Facebook users.
The firm is partly owned by GOP donor and hedge fund billionaire Robert Mercer and his family, and has ties to former and current Trump advisers. Former White House chief strategist Steve Bannon is the firm's former vice president, and White House counselor Kellyanne Conway consulted for the company.
But Trump isn't the only prominent GOP client to pay for services from the firm. Here are other Republicans who have hired Cambridge Analytica. There have been no allegations of unethical behavior by Cambridge Analytica on behalf of these Republican candidates or groups.
Arkansas Sen. Tom Cotton
Cotton paid some $20,000 for Cambridge Analytica's consulting services from 2013 through 2014 as he was campaigning for the Senate.
Sen. Thom Tillis and the North Carolina Republican Party
Tillis and the North Carolina GOP spent $345,000 for "microtargeting" from 2014 through 2015, geared at helping Tillis defeat Democratic incumbent Kay Hagan in 2014, the most expensive US Senate race in history at the time. Cambridge Analytica's website touts the success of their efforts in the race, saying they "were able to design and deploy messages tailored to these audiences according to their particular psychographic profiles."
Make America Number 1 Super PAC
The Mercer-backed Keep the Promise I/Make America Number 1 super PAC paid $1,476,484 to Cambridge Analytica from 2015 through 2016. The PAC funded a series of pro-Ted Cruz ads during the 2016 presidential campaign. The PAC was also led by Conway prior to her joining the Trump campaign.
John Bolton Super PAC
Former US Ambassador to the United Nations John Bolton is being considered to replace H.R. McMaster as White House national security adviser. According to FEC filings, Bolton's super PAC doled out $1,152,299 for Cambridge Analytica's work from 2014 through 2016. All of the services billed are for "research" and "survey research."
Ted Cruz and Ben Carson
During their 2016 presidential campaigns, Texas Sen. Ted Cruz and Dr. Ben Carson solicited Cambridge Analytica for media services, survey research, web services and database management. The Cruz campaign directly spent $5.8 million for the firm's services. In addition, Keep the Promise II super PAC, which is associated with the "Keep the Promise" network of the Mercer-backed PACs, was funded by Cruz supporter and Texas billionaire Toby Neugebauer. The PAC paid $570,000 for Cambridge Analytica's services -- the largest expenditure for the PAC during the election cycle.
Carson, meanwhile, spent $438,065 for the firm's work.