They will survive and put out new growth if they weren't eaten to the ground. I have 4 in containers that were topped just as they were forming flowers. They started putting out new leaves within a week.
Of course, you'll have to give them some kind of protection from the deer for a while. I draped tulle netting over mine. It's very light(and cheap). You can find it at fabric stores or Walmart in the fabric section.

Yes they definitely will, unless as noinwi said, they were eaten to the ground.

I would have eaten my first Sungolds this year had the deer not topped both plants earlier this spring. But now the plants are monsters with probably hundreds of fruit and flowers and it's not too long before they start ripening...

Yeah they will survive. I had a deer or "multiple" deer come in and do a number on my small tomato plants. maybe about 20 plants were hit hard. Some of them didnt even have any leaves left. i think 19, of the 20 recovered. And they are doing well. Ive since made a homemade concoction of two beaten eggs, 2 cups milk, 2 cloves garlic, chopped up in a food proccesor then squeezed through a nylon sock to remove any chunkys. i then added a couple tasblespoons of various hot sauces, a tablespoon of dishsoap and a few cups of water to dilute this solution into a sprayable form from a spray bottle.

I spray this stuff on the tomato plants that were hit by these rampaging fiends on a regular basis with a light to moderate mist. Especially after a rain since the essence of my product will have been washed away. Also i have pieces of ivory soap scattered about in a defensive perimeter guarding the area.

Im not saying these methods are guaranteed. But for three weeks now my tomato plants have not been scavenged at all.

I haven't put up a fence yet around my new garden. But after I had 2 trampling injuries about 10 days ago--I replanted both, and they're doing well now--I strung up about 4 lines of yellow baling twine around the perimeter. It's not very sturdy, but so far it seems to be keeping them out. But I did have another one that just missed getting stepped on a couple days ago. It was bent over a bit, and there was a really small hoof print next to it. Then I was on my way out there again today, and I saw this cute little deer with it's mom. It was probably about a foot and a half tall, maybe half the size of my 55 pound dog. They were both grazing just outside the twine. I think the mother stayed out, since there's really no reason yet for her to go in. But the little one probably walked right under it, since the bottom line is about 18" off the ground. I might add one more line along the bottom, now that I know there's a little one running around. I'll be putting up a fence before my plants get much bigger. But if you need some cheap protection, and in a hurry, you might want to try baling twine. Or some people use monofilament fishing line.

as a followup to the posting of Shoontok (6/23/10), I live in the CA mountains at 2800 feet ~ lots of deer. We have an 8-foot fence, but as I had three tomato plants and 45 Oklahoma rose buds about to bloom on six bushes, someone left the gate open. His recipe is perfect; however, I also add 1 cup of Listerine and let the full concoction sit in the sun for a few days, full strength. Put into sprayer & add water. Everything that had been sprayed was not touched, i.e., Tiger Lilys (deer candy), other roses, etc. Just be sure to reapply after hard rain.

I forgot to spray after a heavy rain and the deer lopped the tops off of my tomatoes and even thorny zucchini leaves! they didn't get to the rest of the plant because of the cage. But you gave me hope...thanks!

I like the enviro friendly post by Shoontok and have seen Irish Spring Soap work as well as Ivory but if the little beasties come back I will be using that recipe Shoontok posted for sure!! Thank God it was only one tomato plant and one Oriental lily. Got 13 tomato plants but 10 behind fencing that I hope will deter them as we are right near the woods. I am trying to use water from bathtubs/kitchen sink to give all plants water, its hard work too. Water bills are ridiculous here in O.C., NC!

Craig LeHouliller says the only thing that really works for him is the Scarecrow motion-activated sprinklers. Environmentally no problem, doesn't hurt the deer, easy once set up.

I also have seen the idea of planting a deer "fence" with all kinds of yummies for the deer that basically stop them before they get to your garden. That could work if one has a fairly large property.