Del. Joseph D. Morrissey (D-Henrico) speaks to reporters, with members of New Kingdom Christian Ministries, in Henrico County on Sunday. Morrissey announced Thursday that we would resign his Virginia House seat. (P. Kevin Morley/ASSOCIATED PRESS)

(Updated: Morrissey no longer allowed work-release during jail term)

State Del. Joseph D. Morrissey, fresh off a misdemeanor conviction stemming from his relationship with a 17-year-old girl, agreed Thursday to step down, and Virginia’s Capitol heaved a sigh of relief.

Until the Richmond Democrat promised to run again next month.

Virginia is in for more spectacle, on top of all the rest: a state delegate sent to prison for corruption; a federal investigation, just wrapped up without charges, that exposed a seeming bidding war over a state senator; and, most shocking of all in a state long known for clean government, the federal corruption conviction and imminent sentencing of a popular former governor and first lady.

The Morrissey affair seemed like a fleeting sideshow to those weightier scandals when it emerged in the summer. He had been in trouble many times before — he’s been jailed for fights and lost his law license for nearly a decade — so it was not a shocker to see him in it again.

But the saga has churned on in ever more salacious and absurd directions, giving it a staying power and a level of attention mortifying to people steeped in the state’s proud image of political rectitude.

There were the nude photos and explicit text messages that prosecutors said Morrissey and the girl exchanged — and a claim from the delegate that their phones had been hacked by the girl’s spurned lesbian ex-lover. There is the girl’s pregnancy, and the prosecutor’s claim that the child is “perhaps” Morrissey’s. (The delegate isn’t saying.)

And most startling of all was the prospect that Morrissey, sentenced to six months in jail but able to leave daily on work release, could show up at the Capitol by day to pass laws — and sleep behind bars at night for breaking them.

“It hurts. It does hurt for people who care about the commonwealth,” said House Clerk G. Paul Nardo, speaking not just about Morrissey but also about the other scandals. “I don’t think this is ‘Schoolhouse Rock.’ We didn’t have this kind of stuff, at least not when I was watching TV on Saturday mornings.”

After Democrats and Republicans alike called on Morrissey to step down, it appeared that he was bowing to that pressure. He told leaders of his own party and House Speaker William J. Howell (R-Stafford) that he was quitting. Morrissey summoned Nardo to his Capitol Square office Thursday and handed him a brief letter of resignation.

Then Morrissey turned around and held a news conference. In one breath, he told reporters that he was resigning, effective Jan. 13, “because of the respect I have for this institution and because I don’t want to be a disruption in the 2015 General Assembly session.” In the next, he threw his hat into the ring.

“Consistent with what I have maintained all along, that it is the voters and not political pundits and not partisan caucuses that should decide who serves in office, I hereby announce my candidacy for the 74th House of Delegates seat to be held in the special election on Jan. 13, 2015,” he said.

Democrats and Republicans, who agree on little else in Richmond lately, were stunned.

“He didn’t tip his hand to me or the speaker,” Nardo said. “There was a lot of shock and surprise that he chose this.”

Democratic leaders had released a statement commending Morrissey for his decision to step down before learning that he still hoped to hold the seat, said the caucus chairman, Scott A. Surovell (Fairfax).

“This stunt is certainly not going to help his situation,” Surovell said. “I suspect . . . if he returns to the legislature he will be facing the exact same expulsion hearing.”

Gov. Terry McAuliffe (D) repeated his call for Morrissey to leave — for good.

“The governor was clear in his statement that Mr. Morrissey should resign,” said spokesman Brian Coy. “That remains his position and he’s hopeful that we can move on from this episode without further embarrassment to this commonwealth.”

Howell, who called the special election for Jan. 13 upon receiving his resignation letter, was even more blunt.

“Mr. Morrissey’s decision to run in this election is deceitful, selfish and disrespectful to this institution and the people he supposedly desires to serve,” Howell said. “This is a despicable, arrogant political stunt that should disgust each and every citizen of Virginia. The people of the 74th district deserve better than this and the obligation now rests with them to retire Mr. Morrissey permanently.

Morrissey, known for long-winded floor speeches and for brandishing an assault weapon in the House chamber as part of a pitch for gun control, has never been widely popular even among Democrats. The latest twist triggered some gallows humor amid scandal-weary Virginia politicos.

Tucker Martin, who was spokesman for former governor Robert F. McDonnell (R), took to Twitter to propose a campaign slogan for the delegate: “Joe Morrissey 2015: It COULD Be His Kid; He SHOULD be Your Delegate.”

McDonnell and his wife, Maureen, were convicted of corruption in September for accepting $177,000 in gifts and sweetheart loans from a Richmond businessman. Their trial, which featured a lurid defense premised on marital woes, stained state’s cherished good-government reputation.

A series of other, smaller scandals only added to the disgrace. In 2011, then-Del. Phillip A. Hamilton was sentenced to nearly a decade in federal prison after his conviction on bribery and extortion charges.

And for the past six months, federal investigators probed whether Republicans had lured a Democrat to quit the state Senate, throwing control to the GOP, with the promise of jobs for himself and his daughter. The investigation ended last week with no charges, but Democrats were shown to have suggested jobs to try to keep him in the Senate.

Paul Goldman, Morrissey’s law partner and a former Democratic state party chairman, was one of the few political voices to take up for him.

“If the voters of the 74th district, knowing what they know, re-elect him, what right does the General Assembly have to throw him out?” Goldman said. “I’m a little amused. I have more confidence in the people of the 74th district than the rest of the Democratic Party and that’s unfortunate.”

Should Morrissey win back his seat, he could still face expulsion, which requires a two-thirds vote and would make him the first member forced out of the House since Reconstruction.

But it could be politically more difficult for the House to oust Morrissey if voters embrace him, warts and all, in the special election, said John McGlennon, chairman of the government department at the College of William and Mary.

“It’s one thing to remove someone from office when information has come to light in the middle of a term,” McGlennon said. “But once the voters have said, ‘Yes, maybe he did something wrong, but we want him to represent us anyway,’ that takes precedence.”

Morrissey was convicted last Friday on a charge of contributing to the delinquency of a minor under a plea agreement in which he maintained his innocence. He was given six months of jail time, with a work-release arrangement that allows him to spend 12 hours a day, seven days a week either at his law firm or his legislative office. He will thus be running his special election campaign while incarcerated.

In his remarks Thursday morning, he emphasized that it would be unprecedented for the House of Delegates to expel a member over a misdemeanor conviction.

Prosecutors initially charged Morrissey with four felonies along with the misdemeanor, including supervisory indecent liberties with a minor, electronic solicitation of a minor, and possession and distribution of child pornography. That final charge, which carries a five-year mandatory minimum sentence, stems from a nude photograph of a 17-year-old receptionist that prosecutors contend Morrissey showed to a friend.

Morrissey, 57, has maintained that incriminating phone messages were planted by a jealous ex-girlfriend of the 17-year-old. The teen herself is defending Morrissey, saying she lied to him about her age and initiated a romantic encounter that stopped short of sexual intercourse.

The circus could come to a close next week, when parties choose nominees for the seat. Nominees must be chosen by 5 p.m. Tuesday, Democrats say, giving both party and candidates little chance to organize. Two Democrats and one Republican have already lined up to challenge Morrissey in the overwhelmingly Democratic district. Financially, Morrissey has a head start, with $90,000 in his campaign chest as of July.

Del. Joseph D. Morrissey's letter of resignation. (Office of Del. Joseph D. Morrissey)