Some legal experts say Comey's testimony -- while remarkable in many ways -- didn't move the needle on that precise question.
"In one key respect, all of today's drama was anti-climatic, because Comey couldn't really speak to the single most important question about obstruction -- whether the President fired him out of a desire, however uniformed or misplaced, to alter the course of the Russia investigation," said Steve Vladeck, CNN legal analyst and professor at the University of Texas School of Law.
But that's not unexpected for someone who is simply a fact witness, said former federal prosecutor Renato Mariotti. Comey wasn't there, Mariotti said, to reach a legal conclusion.
Senators nevertheless tried every way they knew how to press Comey to weigh in on the issue -- especially when it came to the President allegedly saying to Comey in February that former national security adviser Michael Flynn had "been through a lot" and "I hope you can let this go" -- a reference Comey understood to mean the FBI's investigation (and which the President's personal lawyer, Marc Kasowitz, disputes).
But Comey declined to reach a conclusion on whether that request amounted to obstruction, instead repeatedly deferring to special counsel Robert Mueller's ongoing investigation.
"I don't think it's for me to say whether the conversation I had with the President was an effort to obstruct," Comey said.
"I took it as a very disturbing thing, very concerning, but that's a conclusion I'm sure the special counsel will work towards to what the intention was there and whether that's an offense."
Legal scholars all agree that an evaluation of Trump's intent is the key to the entire case.
"Ultimately, the fundamental issue is whether Trump fired Comey with a 'corrupt' intent, meaning to obstruct or impede the federal grand jury investigation," explained Jimmy Gurulé,
a former federal prosecutor and now law professor at Notre Dame.
"President Trump attempted to interfere with and derail a pending criminal investigation targeting General Michael Flynn for reasons unrelated to the merits of the case, Gurulé
added. The cumulative evidence on the matter clearly establishes a prima facie case of obstruction of justice."
And when it came to assessing the President's intent -- Comey didn't hold back and said the fact that Trump shooed everyone out of the Oval Office before telling Comey to ease off Flynn was a "really significant fact."
"Why did he kick everybody out of the Oval Office? Why would you kick the attorney general, the chief of staff out to talk to me if it was about something else?" Comey mused. "So, that to me, as an investigator, is a very significant fact."
So what is Mueller likely use to investigate the President's intent?
"I expect Mueller will look at the President's statements and actions before and after his alleged conversation with Comey, including his dismissal of others from the room and all of the circumstances surrounding his dismissal of Comey," said Mariotti. "He would also seek to interview the President or obtain his sworn testimony before the grand jury to gain admissions from him that could determine his intent."
In other words, Mueller's work has just begun.