Special Counsel Robert Mueller has added another Democrat to his growing team of Trump-Russia investigators.

The former FBI director recently recruited Elizabeth Prelogar, a lawyer in the Office of the Solicitor General, to work on the Russia probe, The National Law Journal reports.

A former law clerk for liberal Supreme Court justices Ruth Bader Ginsburg and Elena Kagan, Prelogar has donated in the past to Hillary Clinton’s and Barack Obama’s presidential campaigns, Federal Election Commission records show.

On Sept. 26, she gave $250 to the Clinton campaign. And on Oct. 3, 2012, she gave the same amount to the Obama campaign and another $250 to the Obama Victory Fund.

Prelogar, who has argued five cases before the Supreme Court, joins a stable of at least 13 other former prosecutors and investigators on Mueller’s staff. Several of the recruits have almost exclusively supported Democratic political candidates.

Trump supporters like former House Speaker Newt Gingrich have pointed to the campaign contributions as evidence that the Mueller investigation will be biased against Trump.

Mueller is reportedly conducting a wide-ranging probe of Trumpworld. He is looking into potential collusion between the Trump campaign and Russian operatives as well as any shady business dealings involving Trump associates. According to some reports, Mueller is also investigating whether Trump committed obstruction of justice in his interactions with former FBI Director James Comey.

As CNN reported last week, at least three of Mueller’s recruits have given more than $53,000 to Democrats since 1988.

James Quarles, a former assistant special prosecutor for the Watergate investigation and a lawyer with Mueller at WilmerHale, has given $33,000 to various Democratic candidates, including Clinton, Obama, John Kerry, Al Gore and Michael Dukakis.

Jeannie Rhee, who served as deputy assistant general in the Obama administration, has given $16,000 to Democrats since 2008. She gave the maximum, $5,400, to Clinton’s campaign in 2015 and 2016. She gave another $7,300 to Obama’s two presidential bids.

Andrew Weissmann, who until recently served as head of the Justice Department’s criminal fraud section, gave $2,300 to Obama’s presidential campaign in 2008 and $2,000 to the Democratic National Committee in 2006.

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Trump supporters have increasingly questioned the political bent of Mueller’s investigative team. Former House Speaker Newt Gingrich has been among the most vocal critics.

Though Gingrich has in the past praised Mueller, he now says he is worried that Mueller will conduct a fair investigation. (RELATED: Gingrich On Russia Investigation: ‘The Fix Is In’)

“So, when you say to me, ‘Do I worry about Mueller as an investigator?’ I think, well, do I worry about a department that’s 97 to 3 [percent], that would pick somebody who’s from a law firm which is 99.81 [percent]? Uh, as a historian, yeah, I’d worry,” Gingrich told The Daily Caller News Foundation in a recent interview. “And then you look at who he hired and it gets worse.”

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