“Man is the only animal that blushes,” Mark Twain said.

“Or needs to,” he added.

Some New York politicians are in a separate class: They’re incapable of blushing. These are people, whether ethically suspect or downright criminal, whose sense of decency has gone haywire. The word “disgraced” has appeared so routinely before their names, you’d think it was what their parents called them. Yet they keep demanding voter affection, having convinced themselves that the city and state cannot possibly get along without them. They’re our zombie candidates.

They’re men like Eliot Spitzer, who forfeited the governorship in a prostitution scandal but somehow had to run for city comptroller in 2013. Or like former Representative Anthony Weiner (Need we really go into detail?), who ran for mayor, also in 2013. Or like Hiram Monserrate, the former City Council member and state senator, who tried last month to regain a Council seat despite his record of misusing public funds and slashing his girlfriend’s face.

Now we have Michael Grimm, a former congressman from Staten Island who spent seven months in a federal prison for felony tax fraud. He said this week that he would try to recapture his House seat by challenging Representative Dan Donovan in a Republican primary next year. Mr. Grimm is in a thuggish league of his own, remembered by many not for his financial finagling but for having threatened in 2014 to hurl a NY1 reporter from the balcony of the United States Capitol for having the temerity to ask a fair question. “I’ll break you in half,” he snarled. “Like a boy.”

In announcing his candidacy, Mr. Grimm apologized for past wrongdoing. He didn’t sound thoroughly repentant, though, essentially calling himself the victim of a political witch hunt who had “the entire Obama Justice Department weaponized against me.” Naturally, he invoked the Republican cliché du jour, promising to “drain the swamp,” despite having been in the muck himself.