MONROE, La. — President Trump on Wednesday continued his attack on a C.I.A. whistle-blower whose complaint prompted the Democratic impeachment inquiry, accusing the official’s lawyer of plotting a coup attempt and denigrating the process as “deranged” and a hoax.

Democrats, Mr. Trump said at a rally in northern Louisiana, are “trying to overthrow American democracy to impose their socialist agenda,” before reading aloud a 2017 tweet by Mark S. Zaid, the whistle-blower’s lawyer. Mr. Trump said the tweet, which was resurfaced on conservative websites, predicted a “coup” and an impeachment, and was proof of a wide-ranging plot against him.

“It’s so bad what they do,” Mr. Trump said. “They rip the guts out of our country.”

In an email, Mr. Zaid, pointed out that he formerly represented the Republican National Committee. He said his tweet was taken out of context and the attacks represented “partisan deflection.”

In the second speech he has given in the state since House Democrats began investigating whether he abused his power by asking the president of Ukraine to investigate Vice President Joseph R. Biden Jr., Mr. Trump sought to tie the state’s Democratic governor to a party he has repeatedly painted as too “delusional” for Louisiana.