Washington (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.

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."

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