Hi, I just posted similar question over on container gardening forum.

I bought couple big pots at H.D. the other day. So gorgeous! Pretty rust colored blooms, with buds just awaiting to pop open, after the original blooms fade--half price, too!

Cause I live in Maine, I placed them close to my house, and, put them on the porch if it's cold at night. Today, it 'snowed' (teensy flakes every now and then. no accumulation) tonight I'll bring in, since they say it'll be 20s. Or, I'll put 'em in greenhouse.
So, maybe we'll get an answer here or there in the other forum.

I cant comment on whether a mum can survive indoors on a slim diet of water and very little...if any at all, sunlight.
If the plants are not those which were grown in a greenhouse simply to provide a little fall color, then it stnads a chance of survival....outdoors.

Mums are outdoor plants and the usual...let's say the common approach, is to --
don't wait for frost to cut them back severely, in a pot or in the soil, place them in a well protected site....such as next to a wall that is out of the way of wind. A good spot is behind foundation plantings. The wall offers a touch of warmth that comes through it, and the protection of not being affected by winter wind, snow, sleet, ...whathaveya...and is buried under soil, leaves, or such for further protection. Further protection from freeze thaw cycles is to place evergreen oughs over it.
If its in a pot, bury the pot in soil. If the ground is too firm to obtain a decent depth, pour warm water over the area until you can open sufficient depth. Depth can also be accomplished by burying in a mound of potting soil.
It is brought out only when no further chance of frost is going to affect it...in the north that would speak for mid to late April---early May even, before it is brought back out, given a place where it can remain, not bothered, and allowed to grow on.
It is then allowed to grow at a pace that allows it to be cut back half its new growth, (about 2"--cut back 1") until about mid August when it is allowed to grow to its full potential.
Flower buds then will be growing on a sturdy, compact bush and will perform much better than if allowed to just grow as it wishes.
By early October it should be ready to be what it was the previous year.

I kept mums alive all winter inside my three season porch. It was a very warm winter. They were three small ones that I put in a window box because we were moving to this place in November, and I never got them planted. I wasn't sure what to do for them, so that was the treatment they got. I made sure they didn't dry out, and they were sitting on a carpet-covered concrete floor under two layers of row cover where they could be in the sun if it shone. They never really did get brown and die back, and one tried to bloom in June I think it was. I just cut them all back then, and planted them in the ground and they got some new growth and are blooming now.

I bought a pot of mums 2 summers ago, thinking they only lasted for one season, and that following fall I just let them die back by themselves (and it really looked dead, just a bunch of short brown sticks)... Well I never got around to throwing them away, and that spring I was getting ready to pull them out of their pot to replace with new plants when I saw new growth, so I just let them be and waited to see what happened. And sure enough they grew back and by very late summer/early fall I had blooms again..

So even if it looks dead by winter, their's still a very good chance they're not. I had them against my back porch wall all winter. You should just put them outside and just let them die back naturally and wait til next spring/summer and see what happens. Alot of people love mums cause of the fact they're so easy to grow back year after year.

I really think leaving them inside is just a for sure death sentence for them, I really do not think they're meant to be kept as houseplants all year long..But that's just from my one experience with them.

-FPT

I believe these are hardy perennials-they die down in winter then sprout again in spring. Not sure how they would work as houseplants-do they need a winter rest?

hey guys, I understand what you all mean-- it's just that I didn't buy any of these beautiful pots (not the jumbo basket size, but the next smaller square pots) all season, because too expensive . . . . . . I liked the way they looked in pots, too and I knew that I really couldn't keep them overwinter.

Right now, just couple days after I bought them at half off, they are beautiful! Full of blooms, with buds already awaiting!!!!
I will enjoy them for as long as I can and will let them die back, I guess (wipes a tear away, sigh.....)

If you let hardy mums naturally go dormant outside, then move them into a garage or storage shed and give them about 1 cup of water once a month until spring and then plant them out in the ground in a sunny well drained place to grow.