Not just any Democratic Senate candidate, either. It’s Richard Blumenthal, current attorney general of Connecticut, whom Chris Dodd made way for by retiring earlier this year. He’s been leading all Republican challengers by upwards of 20 points in the polls and was considered a mortal lock to win the seat in November. Until now.

Follow the link for the full background of his military history. The five deferments aren’t the problem. This is the problem:

“We have learned something important since the days that I served in Vietnam,” Mr. Blumenthal said to the group gathered in Norwalk in March 2008. “And you exemplify it. Whatever we think about the war, whatever we call it — Afghanistan or Iraq — we owe our military men and women unconditional support.”…

In 2003, he addressed a rally in Bridgeport, where about 100 military families gathered to express support for American troops overseas. “When we returned, we saw nothing like this,” Mr. Blumenthal said. “Let us do better by this generation of men and women.”…

The New Haven Register on July 20, 2006, described him as “a veteran of the Vietnam War,” and on April 6, 2007, said that the attorney general had “served in the Marines in Vietnam.” On May 26, 2009, The Connecticut Post, a Bridgeport newspaper that is the state’s third-largest daily, described Mr. Blumenthal as “a Vietnam veteran.” And The Shelton Weekly reported on May 23, 2008, that Mr. Blumenthal “was met with applause when he spoke about his experience as a Marine sergeant in Vietnam.”…

It does not appear that Mr. Blumenthal ever sought to correct those mistakes…

Mr. Blumenthal has made veterans’ issues a centerpiece of his public life and his Senate campaign, but even those who have worked closely with him have gotten the misimpression that he served in Vietnam. In an interview, Jean Risley, the chairwoman of the Connecticut Vietnam Veterans Memorial Inc., recalled listening to an emotional Mr. Blumenthal offering remarks at the dedication of the memorial. She remembered him describing the indignities that he and other veterans faced when they returned from Vietnam.

After five deferments he landed a spot in a Marine Reserve unit based in Washington, “which virtually guaranteed that he would not be sent to Vietnam.” My first thought was whether he might be in violation of the Stolen Valor Act passed a few years ago, but it looks like that only applies to false claims about medals and decorations, not false claims about service. The money question, then: Will this abject disgrace have the honor to resign and bow out of the race or will the Dems stick with him? His lead’s large enough that there’s at least a chance he can weather the storm if he grovels enough. Or actually … there really isn’t a chance, is there? Any other false credential could be spun, but even in a state as blue as Connecticut, lying about military service is just too irretrievably scummy, I think. Vets will eat him for breakfast. Exit quotation from Army veteran Andy Levy, in a tweet to Blumenthal: “You are an utterly despicable coward who claims the bravery and actions of others as your own. Rot in hell.”

Update: It gets worse for Blumenthal. Meet his likely Republican challenger, Rob Simmons:

Rob’s public service career began when he enlisted in the U.S. Army in 1965 as a Private, and spent 19 months in Vietnam where he earned two Bronze Star Medals. Rob continued his military service in the U.S. Army Reserve as a Military Intelligence Officer, retiring as a Colonel in 2003 with over 37 years of active and reserve service.

Update: Credit where credit is due: No doubt it pained the NYT to drop a bomb on one of the few surefire Democratic winners this November, but they dropped it anyway.

Update: Lefty poll guru Nate Silver says Blumenthal must go. It’s really the only sane option. With a state as Democratic as Connecticut, there’s still plenty of time to find a replacement capable of winning the seat. It’s just going to be a closer race than it would otherwise have been, especially now that the military issue will refocus public attention on Simmons’s credentials. Ned Lamont for Senate?

Update: Marc Ambinder quotes Blumenthal’s camp as saying it’s a “hit job” and “full of inaccuracies” with promises of more to come.

Update: Blumenthal’s outrageously outraged — but he doesn’t challenge any of the salient facts. Lights out.

“The New York Times story is an outrageous distortion of Dick Blumenthal’s record of service,” Blumenthal’s campaign manager, Mindy Myers, said in a statement.

“Unlike many of his peers, Dick Blumenthal voluntarily joined the Marine Corps Reserves in 1970 and served for six months in Parris Island, SC and six years in the reserves. He received no special treatment from anyone.”

Previewing a campaign event tomorrow, Myers wrote that “Dick has a long record of standing up for veterans. Tomorrow, veterans will be standing up with Dick.”

Blumenthal will hold a news conference tomorrow. He will be flanked by veterans.