Trailer, you have evidently kept these plants going over winter....which is OK but now you want the plant to be as it was last mid season.
So...cut it back to about 4"...remove all the old flowers, and leaves. Look at those roots---any sign of damage?,..if so remove them. You don't want diseased or damaged roots to feed the new plant. I say the new plant, because that's what you will get...new leaves, new growth, new buds, new flowers.

The plant looks dismal because the sun it got over winter was not sufficient to support growth..and its health suffered.
When you cut it back, you encourage new growth, the plant wants to grow.

Clean pot---it does not need to be small...the plant will grow to fill the average pot....4" if you like, but 6" or 8" is OK too.
New fresh potting soil.....I have no idea what the Miracle Gro potting soil has in it....but generally you can rely on the name...from Scotts...that the M.G. soil is what any plant will grow in.
New plants do not need fertilizer...the fresh potting soil will do that for a time.
Whether the M.G. soil has in it mentioned amounts is neither here nor there.....it is fresh, it is new and it is ready to support new growth.

Cut back to 4"....clean pot, fresh potting soil, shards in the bottom to keep the soil away from plugging up the drainage holes, given the best light you have....a southern, western, or eastern sun will do fine.
Water to drainage, dump the excess, and no more watering until new leaves form. When you water, water always to drainage, dump the excess.

Turn the plant 1/4 turn every day or so....ensuring all parts receive equal sun, and within 2 weeks, new leaves will form. As the plant grows, you can increase food....but not too much...the potting soil will do fine.
Give it 4 - 5 weeks, the plant should have full foliage..and possibly, depending on the strength of the plant, and the sunlight, might form new buds.
In any case, outside when you normally put your annuals out, it will flower up as good as last season.

Don't hesitate to cut it back...it is not in a condition that it will come back the way it is...don't be fooled by seeing a little new growth...that's the sun talking....but it isn't in a condition to go much further.
Cut it back, it will be encouraged to grow...and grow...and will produce flowers like mid season last year.

I guarantee it.

Whether you keep the plant going after you pull it in the fall or not is up to you.
You might consider, if you have a cool place where the plant can be stored...and not face frost, it will do fine until about this time next year when it is brought out, cut back and like above, comes back as good as new.
The storage place should be cool...no frost, dry...and no light.
The pel will go completely dormant...dry up like a prune...and thats the condition you want it to stay.
No need to sprinkle, no need to move it to warmer temp, no need for any light...its dormant...there's no need to encourage development until you want it to.
And that is done in mid February...March...and by mid May it will be ready to go out into the world and produce new flowers.

Pelargoniums are outdoor plants....there is no need to give it a pot that the roots will be so bound to it.
There is no need to put it into such a small pot...the annual will grow. Many people have ONE plant in a large container and surround it with other annuals. Vines especially look good falling over the edge of a container with a geranium flowering out in the middle.

From an old bit of info that I remeber. Geraniums like alkaline soil and they also want a bit of magnesium. Correct me if I'm wrong but thats in my old mental index file. And yes- they like lots of light. They are not light stand plants

I overwintered mine indoors in a sunroom, and they are starting flower now (yay!!!!). I started feeding with 1/2 strength bloom fertilizer (high middle #)every time I water. Bear in mind, some need to be watered less frequently than others. I think it took a month from the time I first noticed the buds to seeing them start to open.

I'm not a fan of MG potting soil by itself for geraniums. I think it needs to be mixed with something so it doesn't hold so much water. The soil I used isn't the moisture retaining stuff, but it still holds too much for a geranium. That's fine (maybe) when these guys are outside in the middle of summer, but for the next 2 months, my 1 unhappy pellie is going to suffer. He was having issues anyway, but this just made it worse IMO.