The President mentioned Hillary Clinton by name on Twitter 28 times in the month of August - the most since October 2016, when he gave her name 123 mentions on his favorite social media site.
"Why Hillary? I think there are two reasons," said Norm Ornstein, a political analyst with the American Enterprise Institute. "The first is that hatred towards her really does animate a large portion of his base."
"The second is it fits his narrative: that the establishment tilted the election in favor of Hillary, and that going after him and not her demonstrates their bias," added Ornstein, who has been a sharp critic of the President.
"I have never ever seen anything like his obsession with Clinton," said Jim Manley, a long time aide to both former Senate Democratic Leader Harry Reid (D-NV) and Sen. Edward Kennedy (D-MA).
"I guess it must play well with his base but to me it reeks of weakness," Manley added. "I can’t imagine this kind of rhetoric will help him to expand to pick up additional support."
At Thursday night's campaign rally in Indiana, the mere mention of Clinton's name by Republican candidate Mike Braun, who is running for U.S. Senate, set off the familiar, "Lock her up!" chant from the crowd.
"Our Justice Department and our FBI have to start doing their job," the President said to cheers as he referred to an investigation of Clinton over her use of a private email server while Secretary of State.
In recent days, the President has pressed stories in conservative circles that the FBI never reviewed all of Clinton's emails, and that the Chinese had hacked her email server.
That accusation drew a firm response from the bureau, as an FBI official told reporters there was never evidence that the Chinese had gained access to the Clinton server.
The President has also used the attacks on Clinton to vent his frustration about the Special Counsel probe into Russian interference in the 2016 elections.
"The only Collusion and Obstruction was by Crooked Hillary, the Democrats and the DNC!" the President wrote in early August.
While some Republicans have egged on the President, GOP lawmakers in the House and Senate have held few hearings on the Clinton email issue, as their calls for a special counsel to investigate the Democratic nominee for President were spurned by Attorney General Jeff Sessions earlier this year.
For those interested in the frequency of how often President Trump has used the word, "Hillary" on Twitter, here is the breakdown of the last two years:
August 2018 - 28 times
July 2018 - 11
June 2018 - 9
May 2018 - 10
April 2018 - 6
March 2018 - 5
February 2018 - 4
January 2018 - 1
December 2017 - 6
November 2017 - 9
October 2017 - 6
September 2017 - 7
August 2017 - 1
July 2017 - 8
June 2017 - 5
May 2017 - 2
April 2017 - 3
March 2017 - 2
February 2017 - 1
January 2017 - 4
December 2016 - 6
November 2016 - 21
October 2016 - 123
September 2016 - 53
August 2016 - 79
July 2016 - 105