Nick Giannis and his son, Chris, are charged with stealing nearly $2 million.
Chris posted bond and was released Friday from Cook County Jail. His father Nick remains jailed in Detroit.
Broadway Bank is not accused of any wrong doing. However, the senior Giannis did contribute to Giannoulias' political campaigns and receive loans from the bank.
Alexi Giannoulias said Friday in a statement he was "shocked and appalled" at the arrests Thursday of principals in the Boston Blackies restaurant chain.
Thirty-eight year-old suspects Chris Giannis and Andy Bakopoulos were picked up in Chicago while Blackies founder 62-year-old Nick Giannis was detained in Detroit allegedly trying to leave the country.
Giannoulias reportedly has known the elder Giannis and son for decades. Not only has Nick Giannis donated $119,000 to Giannoulias' campaigns for treasurer and the U.S. Senate, the Giannoulias family's troubled Broadway Bank has made business loans to the Boston Blackies chain.
Republican Senate candidate Mark Kirk issued a statement Friday headlined "Giannoulias' association with criminals continues." The North Shore congressman said,"Nick Giannis was second largest campaign contributor outside of (the) Giannoulias family?Broadway Bank loaned Giannis roughly $6 million in mortgages...despite his felony conviction in 1996 for illegal firearm possession."
Last Tuesday, the embattled Giannoulias Campaign was buoyed during a White House visit and meeting with President Obama's senior political adviser, David Axelrod, and a Rasmussen poll that showed the Democrat leading Kirk by 3 percentage points.
Friday, Giannoulias was back on the defensive. He called his family's Broadway Bank one of several banks defrauded by the alleged Giannis scheme and he announced that his campaign would immediately "donate all contributions from these individuals to non-profit organizations".
Giannoulias was unavailable for comment Friday. His staff said he was in meetings trying to raise money for his campaign.