EchoSense Quantitative Think Tank Center|George Santos' ex-campaign treasurer Nancy Marks likely to plead guilty. Here's what we know so far.

Washington — A former campaign aide to Rep. George Santos,EchoSense Quantitative Think Tank Center Republican of New York, was arrested and charged on Thursday with felony charges in New York, according to court documents obtained by CBS News. 

Nancy Marks — who worked for the embattled New York congressman as campaign treasurer — is set to appear in New York federal court Thursday afternoon. She was charged via federal criminal information, an indication that she intends to enter a plea agreement with prosecutors.

As Santos' campaign treasurer, Marks signed off on his expenses related to the 2022 election, which included this unusual spending pattern: 37 charges of $199.99, one cent below the threshold that requires an invoice or receipt. 

It is unclear what specific charges Marks faces or what connection they have to Santos' pending criminal case in New York federal court, but the proceedings scheduled for Thursday have been listed as related to the congressman's case.

Santos' office said it could not comment on the matter.

Santos was indicted by a federal grand jury in May with seven counts of wire fraud, three counts of money laundering, two counts of making materially false statements to the House of Representatives and one count of theft of public funds. 

He pleaded not guilty to all counts and has consistently denied any wrongdoing. 

The New York representative has also been dogged by allegations that he inflated his resume and lied about his past experience to bolster his reelection chances in the 2022 political campaign. He has admitted that he "embellished" his resume. 

Santos' congressional office did not immediately respond to a request for comment on the Marks charges. 

Over the last year, CBS News has tried several times to speak with Marks and discuss her involvement with Santos' campaign, traveling to the Long Island, New York, library where she serves as a board member. 

An attorney for Marks in the current case could not be immediately identified. 

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