It’s not quite the welcome back that state Sen.-elect Bill Diamond, D-Windham, expected.

“No kidding around, this is almost a religious responsibility we’ve been charged with,” Diamond said Monday during a hallway interview at the State House. “We’re talking about protecting the sanctity of the voter in Maine.”

Or so we can only hope.

It’s way too soon to drop the f-bomb – as in “fraud” – on last month’s disputed recount in Senate District 25, where 21 “phantom ballots” from tiny Long Island tipped the final tally away from Democrat Cathy Breen of Falmouth and toward Republican Cathy Manchester of Gray.

But as Manchester takes her provisional seat this morning among the Senate’s new Republican majority, two things are already clear:

First, election officials on Long Island have some serious explaining to do.

And second, it looks like the Senate committee charged with unraveling this mess will be up to the task.

Diamond, a longtime lawmaker and former secretary of state who is returning to Augusta after a two-year absence, will sit on the panel alongside fellow Democrats Sen. Stan Gerzofsky of Brunswick and Sen. Dawn Hill of Cape Neddick.

On the Republican side, meanwhile, Sen. Roger Katz of Augusta will chair the committee along with three Republican colleagues to be named this morning by incoming Senate President Michael Thibodeau.

Meaning the days of partisan broadsides – the Democrats have strongly implied there’s something sinister going on here, while the Republicans have insisted it’s much ado about nothing – will finally give way to a far more useful examination of what actually happened out on Long Island just over a month ago.

Cooler heads, most notably seasoned moderates Katz and Diamond, can now take up the daunting task of determining exactly how the District 25 recount produced 21 more ballots than the number of voters who officially showed up at the polls. And how every last one of those extra ballots was marked for Manchester, helping to propel her from a 32-vote deficit before the recount to an 11-vote victory afterward.

“We want to get it right,” Katz said in an interview Tuesday. “It’s about the sanctity of the institution and I think all of us take that very seriously. ”

Echoed Diamond, “We’re simply saying at this point that these questions are too big to hide. We have to answer them.”

Actually, the folks on Long Island have to answer them – starting with Town Clerk Brenda Singo, who served Nov. 4 as the town’s chief election warden.

So far, Singo has done little to dispel the mystery surrounding an anomaly that by most accounts is without precedent in Maine’s recent electoral history.

Case in point: Singo told the Press Herald’s Steve Mistler on Monday that she couldn’t remember the names of the other clerks involved in counting Long Island’s ballots. She then referred all other questions about the vote count to Secretary of State Matthew Dunlap, who last week declared the whole mess “constitutionally in the purview of the Maine state Senate.”

So, with the political currents swirling like an outgoing tide in Hussey Sound, where does a Senate committee begin?

At the very beginning, that’s where. Without a timeline showing exactly who did what from the moment the polls opened Nov. 4 to the moment Long Island’s ballot box was locked and sealed with 171 tabulated ballots purportedly inside, this probe will go nowhere fast.

Beyond that, this is not rocket science. It’s simple math.

Long Island has 238 registered voters. According to the incoming voter list compiled on Election Day, 171 of those voters showed up and cast ballots.

That leaves 67 Long Island voters who either stayed home that day or actually did show up and, for some yet-to-be-explained reason, were not duly recorded as they gave their names and were handed their ballots.

Assuming that’s what happened, it was no small oversight: For the 21 extra ballots to stem from simple inattentiveness on the part of election workers, one out of every 11 Long Island voters would have obtained a ballot without having his or her name checked off.

Diamond applied that same percentage to his hometown of Windham. Had the same thing happened there, he calculated, some 1,300 voters would have passed through the polls unnoticed.

“That would be a phenomenal number of votes we’re talking about,” he said.

Still, given the small population of Long Island, wouldn’t it be relatively easy to canvas those 67 purported no-shows to determine how many, if any, actually voted on Election Day?

“Absolutely,” said Diamond. “I don’t think we should rule anything out as an investigative committee.”

Another troubling question: Is it mere coincidence that the 21 extra ballots, later found atop the last bundle to be counted and certified on Election Night before being placed inside a metal lock box, all showed a vote for Manchester? And while we’re on the subject, were all of the 21 extras marked identically (if at all) in other races up and down the ballot?

Some would suggest that these questions – and the many more still hanging like a thick fog over Senate District 25 – are no big deal.

Maine Republican Party Chairman Rick Bennett, in a strident email blast on Monday, went so far as to dismiss the whole affair as a “dishonest campaign against Cathy Manchester” by Maine Democrats whose “entire communications strategy is now geared toward promoting conspiracy theories about an election recount they lost, partly because 21 votes for the Republican candidate were not suppressed.”

Bennett, himself a former Senate president, should be ashamed of himself. Not to mention a tad embarrassed that on the same day he reflexively punched his party’s “launch attack” button, fellow Republican Katz was already hard at work preparing for the very process Bennett so reflexively condemns.

Katz said the committee, which will have subpoena power, will meet today just to get organized. It will then solicit testimony and other evidence early next week, possibly Tuesday.

“We want to be thorough and fair, but we’re hoping we can complete that in a day,” Katz said.

Here’s hoping it’s a long day.

What truly matters here, after all, is not which party ultimately lays claim to the District 25 seat. Regardless of how this thing ends, the Republicans will remain solidly in control of the Maine Senate for the next two years.

Rather, this is about our very democracy. An election blemished by pivotal numbers that simply don’t add up – be it through simple human error or something much worse – degrades the process for us all.

Diamond appreciates that better than most. He was Maine’s secretary of state back in 1992 when two legislative workers – one a lieutenant to then-Democratic House Speaker John Martin – were convicted of burglary and ballot tampering following their clumsy attempt to sabotage recounts in two Maine House races.

In fact, a bipartisan commission created by Diamond in the wake of what came to be called “Ballotgate” devised many of the safeguards that to this day protect Maine’s typically pristine elections from even the scent of scandal.

“It has nothing to do with Cathy Manchester or Cathy Breen. It has all to do with the people of Maine and the system we have,” said Diamond. “This is really important.”

All those in agreement say “aye.”