Donald Trump's attorneys pushed two legal challenges before Easter weekend, Ednews reports via BBC.
His camp is appealing against a verdict from a Georgia judge allowing Fulton County District Attorney Fani Willis to stay on an election subversion case.
They also aim to stop the expansion of a gag order, limiting Mr Trump's speech, in a New York hush money case.
The Republican presidential nominee faces four legal cases, and these two are the most likely to be heard in court before the US elections.
Mr Trump has pleaded not guilty in all the cases, and claimed he is being politically persecuted.
Mr Trump and his co-defendants in the Georgia case, which accuses them of plotting to overturn the 2020 election, have alleged that Ms Willis financially benefitted from an improper romantic relationship with Nathan Wade - a prosecutor she hired to lead the case.
Judge Scott McAfee - who is overseeing the case - held two weeks of chaotic hearings that included fiery testimony from Ms Willis. She admitted to the relationship but denied benefitting from it financially.
In the end, the judge sided with Ms Willis, though he said the relationship had the "appearance of impropriety" and demanded Mr Wade or Ms Willis step down. Mr Wade did so within hours.
In a 51-page motion filed on Friday before the Georgia Court of Appeals, Mr Trump and eight of his co-defendants argued Ms Willis should also be removed - which would greatly delay the case or could lead to it being dismissed.
Mr Trump and other co-defendants' lawyers said Mr Wade's resignation did not sufficiently address the "appearance of impropriety" that "cast a pall over these entire proceedings".
"The trial court was bound by existing case law to not only require Wade's disqualification (which occurred) but also to require the disqualification of DA Willis and her entire office," the attorneys said in the filing.
CBS News, the BBC's US partner, has reported that Ms Willis intends to play a prominent role in the case, which the judge has ordered to proceed if Mr Trump appeals.
Meanwhile, in New York, Mr Trump is embroiled in other legal battles while he awaits the start of his first criminal trial over the alleged falsification of business records related to a payment made to adult film star Stormy Daniels.
This week, the justice in the case, Juan Merchan, granted a request from the Manhattan District Attorney's Office to impose a gag order on Mr Trump barring him from making statements about jurors and witnesses or intimidating court staff.
On Friday, Manhattan District Attorney Alvin Bragg sought to clarify - and possibly expand - the gag order barring Mr Trump from attacking court staff and their family members.
His motion came after Mr Trump insulted Justice Merchan's daughter in a social media post before the gag order was issued.
Mr Bragg asked Justice Merchan to "make abundantly clear" that the gag order applied to "family members of the Court", the district attorney and other individuals mentioned in the gag order.
He also asked the judge to "warn" Mr Trump "and direct him to immediately desist".
If Mr Trump does not, the prosecutor argues, he should face sanctions.
The former president's attorney, Todd Blanche, denied that his client had violated the gag order and argued that the judge's daughter was not a part of it.
He wrote that there was nothing wrong with the social media posts.
"Contrary to the People's suggestion, the Court cannot 'direct' President Trump to do something that the gag order does not require," he said.
