QUINCY — Sen. Bill Nelson campaigned in rural Quincy Monday night, still fielding questions about his claim that Russians have penetrated Florida's elections apparatus in the current election cycle.

Ending an unusual period of silence that began last Thursday, Nelson spoke to reporters before meeting with a group of Quincy-area Democrats. But he chose his words with great care and said little that was new.

"It would be foolish to think that the Russians would not continue to do this as they did in Florida in 2016," Nelson said.

Pulling an index card from his pocket and checking his handwriting, he said of Gov. Rick Scott: "The word is unfortunate. It's unfortunate that some Florida officials are trying to use this for partisan political purposes."

READ MORE: Rick Scott demands Bill Nelson provide proof of meddling

Nelson disappeared from view last Thursday, reportedly to keep earlier commitments to film TV ads. On Monday, he sidestepped a charge by Scott that the senator might have released classified information. Nelson said he hasn't spoken with Florida's other senator, Republican Marco Rubio, since the story broke last Wednesday.

On Monday it was the state's turn to be silent on questions of election meddling. Scott's chief elections official, Secretary of State Ken Detzner, gave the FBI and Department of Homeland Security till 5 p.m. Monday to respond to a lengthy letter the state sent last week.

Detzner's office did not respond to three requests for comment Monday. His spokeswoman, Sarah Revell, said Tuesday morning that the two federal agencies did not respond by the state's Monday deadline.

Senate Intelligence Committee Chairman Richard Burr, R.-N.C., issued his own statement Friday that neither confirmed nor contradicted Nelson's unproven claim and made reference to "Russia's continued efforts to interfere in our democracy and undermine our elections."

Senate Intelligence Chairman Burr responds to Florida’s chief election official: pic.twitter.com/rCqdXB885i — Alex Leary (@learyreports) August 10, 2018

But the state, in its Aug. 10 letter seeking a response from the FBI and DHS, said: "The Department received a swift response from Senator Burr that did not confirm Senator Nelson's statements."

Nelson reiterated that Burr and the Intelligence Committee's ranking Democrat, Sen. Mark Warner, D-Va., "came to us (Nelson and Rubio) back in June" and urged them to send a letter to Florida election supervisors that encouraged them to reach out to the feds for cyber-security assistance. The letter was dated July 2, and some supervisors have said it was too vaguely-worded to warrant a specific response. Nelson suggested Monday that the vague wording was done for national security reasons.

This hornet's nest of a story isn't going away. On MSNBC Monday, Rachel Maddow showed an outline of Florida and Nelson's words to the Times last week — "They have already penetrated certain counties" — superimposed on it. Said Maddow: "Senator Nelson is standing by this very provocative claim."

Nelson travels to four North Florida towns on Tuesday in an old-fashioned grass-roots campaign. He planned visits to Monticello, Madison, White Springs and Starke. The meddling question is likely to come up again.