The judge responsible for Donald Trump's upcoming sentencing, Juan Merchan, is under mounting scrutiny for his ties to Democrats including Kamala Harris.

Juan Merchan has declined to step aside from the "hush money" case, despite the apparent conflict of interest. But Republicans are drilling down with a subpoena to his daughter Loren Merchan's Democratic consulting company, Authentic Campaigns.

Loren Merchan is president and minority partner of the company, whose current and past clients include Adam Schiff (D-Ca.) and Kamala Harris' 2020 presidential campaign.

Judge's Kamala connection

House Judiciary chairman Jim Jordan (R-Oh.) subpoenaed the company's founder and CEO, Michael Nellis, also a top adviser on Harris' 2020 campaign.

The subpoena demands "all documents relating to the company’s connections with the Biden-Harris campaign, any correspondence with Judge Merchan, and any document that refers to the indictment of Trump," according to CNN.

In a letter, Jordan made note of Merchan's daughter's work "on behalf of President Trump’s political adversaries and the possible financial benefit that Ms. Merchan and Authentic Campaigns received from the prosecution and conviction of President Trump."

Jordan said the company's refusal to comply with past requests left him no choice but to issue a subpoena. Nellis furiously dismissed the letter and Jordan's probe as a political hit job.

“Let us be clear: these allegations against our company are completely false and purely politically motivated,” he wrote. “This is a blatant attempt to intimidate us and divert attention from Donald Trump’s conviction.”

Merchan won't step aside

Throughout the trial, Judge Merchan consistently ruled against Trump, who complained the judge was against him.

Merchan placed Trump under a gag order before the trial and then expanded it to prevent Trump from talking about Merchan's family, after Trump criticized his daughter's work.

Merchan has yet to fully release Trump from the gag order, and he has declined Trump's requests to step aside, saying there is no conflict despite Trump's matchup with Kamala Harris in the fall.

Harris has used Trump's conviction to attack Trump on the campaign trail, and Democratic clients of Authentic Campaigns have raised millions off of the case.

Merchan is expected to sentence Trump on September 18, although some speculate the sentencing will be delayed over Trump's likely appeal of Merchan's pending ruling on a motion to dismiss the charges.