June 2016: “It was the D.N.C. that did the ‘hacking.’”

The Democratic National Committee said that Russian hackers had obtained a trove of internal emails and opposition research. In response, Mr. Trump suggested that the D.N.C. fabricated the story or did the hacking itself:

“We believe it was the D.N.C. that did the ‘hacking’ as a way to distract from the many issues facing their deeply flawed candidate and failed party leader. Too bad the D.N.C. doesn’t hack Crooked Hillary’s 33,000 missing emails,” Mr. Trump said in a statement on June 15, referring to Hillary Clinton, his Democratic opponent.

September 2016: “I don’t think anybody knows it was Russia that broke into the D.N.C.”

As the presidential nominees of their political parties, Mr. Trump and Mrs. Clinton began receiving government intelligence reports in August. On Sept. 22, top Democrats on congressional intelligence committees issued a public statement blaming Russia, “based on briefings we have received.”

Four days later, during the first presidential debate, Mr. Trump declined to agree:

“I don’t think anybody knows it was Russia that broke into the D.N.C. She’s saying Russia, Russia, Russia, but I don’t — maybe it was. I mean, it could be Russia, but it could also be China. It could also be lots of other people. It also could be somebody sitting on their bed that weighs 400 pounds, O.K.?”

October 2016: “Maybe there is no hacking.”

On Oct. 7, the United States intelligence community released a statement saying it was “confident that the Russian government” directed the cyberattacks.

Two days later, Mr. Trump again expressed doubt during the second presidential debate that Russia was responsible:

“But I notice, anytime anything wrong happens, they like to say the Russians are — she doesn’t know if it’s the Russians doing the hacking. Maybe there is no hacking. But they always blame Russia. And the reason they blame Russia because they think they’re trying to tarnish me with Russia.”

December 2016: “I don’t believe they interfered. That became a laughing point, not a talking point, a laughing point.”