The Senate Leadership Fund super PAC ripped Florida Sen. Bill Nelson (D.) as "no longer dealing from a full deck" on Wednesday in its latest attack on the 75-year-old lawmaker as out of touch and confused.

The group, which boosts Senate Republicans, highlighted a Tampa Bay Times article pointing out Nelson criticized his 2018 opponent, Gov. Rick Scott (R.), for lobbying the Environmental Protection Agency in 2010 to delay a new set of stricter water standards. The catch: Nelson wrote the EPA before Scott did to make a near-identical request:

Nelson wrote a strikingly similar letter to the EPA, before Scott. The senator noted that at the time, EPA was getting lots of negative comments about the new rules from local governments, businesses and agricultural interests in Florida amid fears that the standards could apply to drainage ditches and discharges from treatment plants. "Clean water is a goal we all share," Nelson told the EPA on Sept. 16, 2010. "That is why it is imperative that this regulation is finalized in a deliberative manner, utilizing sound science and considering the effects of implementation. Rushing to finalize the rule could result in further uncertainty and unnecessary economic hardship for municipal government and Florida industry."

Nelson "said he did not recall writing it and said he would have to look into its origins" when asked about the letter, according to the Times.

"It’s time for Bill Nelson’s caretakers to keep better tabs on the Senator’s whereabouts and public statements so that he is not embarrassed into admitting he’s no longer dealing from a full deck," SLF spokesman Chris Pack said in a statement.

The SLF email included other examples of the Democrat seeming out of the loop, such as when Business Insider reporter Joe Perticone said Nelson didn't know what the Chinese telecom firm ZTE was. Many analysts and lawmakers have targeting the firm as a national security threat. Nelson is part of the Finance Committee's subcommittee on international trade.

Bill Nelson, who sits on the Finance Committee’s subcommittee on international trade, just told me he doesn’t know what ZTE is… — Joe Perticone (@JoePerticone) May 17, 2018

"Bill Nelson is losing it and needs to retire," Pack said in May.

SLF also slammed him in July for giving a series of shifting positions on Supreme Court nominee Brett Kavanaugh. He called Kavanaugh a right-wing extremist after saying he would withhold judgment on his nomination until they met.

Nelson is seeking a fourth term in the U.S. Senate, but he faces a difficult re-election battle against Scott. Scott is concluding his second term as Florida governor this year and has held a narrow lead in recent polling.