Monday, the secessionist movement gets its first real test of popular support on the Islands.

Or will it be the popular support of redistricting that is on trial?

No one seems certain.

Rep. Terrence P. McCarthy, this week: “A vote for secession is a vote against the redistricting plan.”

From the governor’s office of New Hampshire, unofficially: “Are you serious about secession, or are you angry about the reapportionment?”

An Islander: “Between you and me, I hope we don’t get a representative — if we do, that will kill the movement, and I’d like to get out of this state.”

From another: “The whole thing is a lot of nonsense.”

Whatever the test is, it comes Monday.

Chilmark and Gosnold voters at their town meetings, and Nantucket voters in their town elections, will say yes or no to the question: “Due to the present plan of the Massachusetts legislature to disenfranchise the voters of the town you wish to secede from the commonwealth?”

Representative McCarthy’s telephone poll, the only measure of opinion at this point, continues. As the count goes up and the time goes on, the proportions remain about the same: 60 per cent in favor of secession, 20 per cent opposed, and 20 per cent undecided.

New Hampshire joined the growing list Tuesday, when its House of Representatives passed, by an over­whelming majority (“virtually unanimous,” said one person) a resolution inviting the Islands to join “this nation’s most democratic state.”

In all these invitations, there has been a strong vein of humor. If Islanders aren’t taking the whole thing too seriously, no one else wants to be caught doing so.

If the tongues come out of cheek, it won’t be until after the returns from Monday’s votes are in.

From the office of the Nantucket selectmen a letter went out Friday to the governors of all the New England states, thanking them for their interest, saying the selectmen would like to meet with representatives if the matter comes to serious consideration, but, in effect, “We’re not doing anything more until the voters have their say.”

On the other end of the stick, Gov. Richard A. Snelling of Vermont said pretty much the same thing in an in­formal telephone conversation yesterday. “Vermonters aren’t pushy. We won’t be down to talk until we have a formal invitation.” Then he added that some secession bumper stickers shipped from the Island to Vermont early in the week have all been snapped up.

In Boston, the same sort of waiting is going on. Rep. George A. Keverian is still at work on his redistricting plan, and won’t say when it will be on the floor for a vote.

Early in the year, Mr. Keverian said he wanted to get it through the house as quickly as possible, and indicated he wouldn’t even wait for the return of house speaker Thomas McGee, if he didn’t have to. He said the longer the plan sat, the more time people would have to become unhappy about it.

People are unhappy about it, people besides Islanders. Observers say that the moment Mr. Keverian thinks he has the necessary votes to get his plan through, he will have it on the floor.

Question: Can he gain more votes by shuffling the district borders than he loses by the delay — and the reshuffling?

And, suppose the legislature doesn’t pass any redistricting plan by the late spring of next year?

Rep. McCarthy says two things might happen in that case. The Supreme Judicial Court might impose a plan on the state, or there might be a state-wide election of representatives-at-large.

But that is far off. More immediately, Representative McCarthy has another idea in the works. When (and if) Rep. Keverian does introduce a plan, Mr. McCarthy will introduce a bill asking that action on the plan be delayed until the Supreme Judicial Court is asked whether giving the Islands their own representative would be unconstitutional.

I think it would pass. A lot of people are sympathetic to our cause. Leadership is saying they can’t consider giving us a representative because it might be unconstitutional. The least they can do is agree to ask the court whether they are right or wrong,” Mr. McCarthy says.

At a press conference on the Island Saturday, the old question came up again: “Are you serious?”

Mr. McCarthy, in answer: “Our problem at first was that people thought this was a joke. It isn’t. We wanted to dramatize the problem. Was it a publicity stunt? Well, yes — we wanted to get the attention of the people. But the colonists started out just to get the people’s attention. But, parliament refused to listen.”

The press conference itself was an indication that Representative McCarthy, at least, thinks people are taking the secession possibility more and more seriously. “When we call up people for our poll, we are getting more and more questions like ‘What about my pension?’ and ‘Can we really do it?’ “ he said.

Here are some of his answers:

Can we do it? Yes, we can legally secede. It takes a vote of the state legislature, and a vote of congress.

What about finances? That is a tough one: the state apparently keeps no records of total disbursements or total receipts, county by county, and many of the figures can’t be extracted. Maybe a better way to answer it is for each voter to think it out for himself, always asking whether it is state, or federal money that he gets back in return for his taxes. The state simply acts as a conduit; the conduit has sticky fingers.

What about pensions? If you are already earning a pension, nothing happens. You would still get it if you moved to Florida, for example. The county pension system is locally financed; nothing changes there.

People still working, who are on the state pension system, could withdraw what they have paid in so far, and add it to the pension system of any new state the Islands join, and be received into that system without loss of benefits.

What about licenses? As part of the initial agreement, any new state we join would be asked to accept into their own system, under a grandfather clause, all current license holders — lawyers, plumbers, real estate agents, automobile drivers, and so on.

What about students at the state colleges? The New England states now have a reciprocity agreement whereby a student from, say, New Hampshire, can attend a state college in, say Massachusetts, and pay no more than a Massachusetts resident would pay, if his own state college doesn’t offer the program he wants.

The details can be worked out in negotiations. In principle, we would have the same rights as any other citizen of the state we join, Mr. McCarthy said.

But first, are we serious? Is New Hampshire serious?

Monday will tell something about us. Here is part of the New Hampshire resolution passed Tuesday:

. . . Whereas, the people of New Hampshire have long looked upon their neighbors to the south with a compassion to be expected from citizens of this nation’s most democratic state;

And whereas, New Hampshire’s long tradition of providing a haven for the oppressed and the disenfranchised makes the people of this state particularly sensitive to the plight of nonresidents of New Hampshire;

And whereas, the addition of the islands to the coastline of New Hampshire would increase by more than 15 increased weight in national and international affairs;

And whereas, the addition of the 250 miles of coastline of these two islands to the coastline of New Hamp­shire would increase by more than 15 times our state’s present coast line;

And whereas, the adoption of the 14,000 people inhabiting these two Islands into the citizenry of New Hampshire would, under our formula for representation in the House of Representatives, give the people of these islands eight representatives in the House while they have not a single representative on the General Court of Massachusetts, and would evidence to the nation our superior system of government;

Now, therefore, be it resolved: That the state of New Hampshire offer to the people of the Islands of Nantucket and Martha’s Vineyard full rights of citizenship in the State of New Hampshire upon their taking an oath of allegiance to the free, independent, sovereign — and friendly — state of New Hampshire.”