While Democrats pressed Comey over how the FBI dealt with the Clinton email server matter - saying people were "confused and disappointed" - the FBI chief also took flak from the top Republican on the Senate Judiciary Committee over the handling of the probe into links between Russia and the campaign of President Donald Trump.
"It was a hard choice - I still believe in retrospect, the right choice - as painful as this has been," Comey said, not budging from his decisions.
Supporters of Clinton were clearly not swayed by the FBI Director's explanation.
While Democrats were aggravated with Comey, there was grumbling from Republicans as well over how the FBI dealt with questions about Russia and the Trump Campaign.
"So, a cloud of doubt hangs over the FBI," said Sen. Charles Grassley (R-IA), who started the hearing by raising questions about the "Steele Dossier," a private intelligence review undertaken by a former British Intelligence official.
Grassley also directly pressed Comey on whether he and his top aides had been leaking information from the Russia investigation about aides to the Trump Campaign - Comey's response was he was not giving reporters any information.
Republicans also pressed the FBI Director on why charges weren't filed against former Clinton aide Huma Abedin, over her handling of classified information, some of which showed up on a laptop owned by her former husband, ex-Rep. Anthony Weiner (R-NY).
In exchanges with Sen. John Kennedy (R-LA) and Sen. Ted Cruz (R-TX), Comey said the FBI did not pursue charges against Abedin, because the feds could not "prove any sort of criminal intent," an answer that didn't sit well with GOP Senators.
Comey said the same about the underlying investigation of Hillary Clinton as well.
"I believed what I said," Comey told Senators. "There was not a prosecutable case there."
As for the probe of Trump-Russia links, the FBI Director offered little in the way of new information about the investigation, simply again confirming that there was an ongoing probe, and once more denying that there was any surveillance in 2016 of the Trump Campaign.