“Tricky Dick,” indeed.

During his time in the White House, President Richard Nixon — pug-nosed, jowly, irascible, charmless-yet-devoted husband to Pat — was known to awkwardly hit on middle-aged female staffers.

In “The Last of the President’s Men” (Simon & Schuster), veteran journalist Bob Woodward quotes Alexander Butterfield, Nixon’s deputy assistant, about the commander-in-chief’s sad seduction techniques.

Nell Yates was a 48-year-old secretary who had been at the White House since Truman was president. She was no one’s idea of a sex bomb — she wore her hair in a tight bun and had a stern presence.

Nixon had a crush.

One Saturday night, in the spring of 1972, Nixon summoned Yates to Camp David.

“She came back three hours later,” Butterfield told Woodward. “She was a pretty cool person to be really distraught, openly distraught, but said, ‘Ugh, the most painful, uncomfortable evening of my life.’”

Butterfield asked her if the president had made a move on her.

“An awful lot of starting to make moves and then withdrawing,” Yates said. She couldn’t wait to be dismissed.

That same month, Nixon creeped out another female staffer: secretary Beverly Kaye, 42, who had the thankless task of flying on Marine One from Camp David to the White House. Butterfield was also on the flight.

It was a very long 20 minutes.

Kaye was wearing a miniskirt. Nixon openly ogled her.

“Beverly, why don’t you sit up here with us?” he asked.

But as soon as Kaye sat down, Nixon began staring at her thighs.

“And finally, just out of the blue . . . he starts patting her on her bare legs,” Butterfield told Woodward. “In the manner of patting a young girl, like a 4-year-old girl.”

Nixon’s conversational style was as juvenile.

“Well, did you enjoy Camp ­David?” he asked. “I guess there wasn’t much to do. I apologize for that. Because it can get boring up here.”

He kept on patting her thighs and chattering away. Butterfield was seated right next to Kaye.

“She has stiffened up like you can’t believe,” Butterfield said. “She’s petrified.” It went on for at least 10 minutes, he said.

Female underlings weren’t the only ones who thought Nixon was a bumbling ladies’ man. While on a trip to the Caribbean, two of the president’s friends found Nixon so sexually immature that they put a blow-up doll in his bed.

But the groping on Marine One solidified Butterfield’s disgust with Nixon — two years before the president would resign over Watergate.

“In this moment,” he told Woodward, “I just thought, ‘The poor, pitiful son of a bitch.’”