Technically they don't survive winters, they are an annual. But they will seed themselves and that seems to be what happened in your case.

To the best of my recollection, Gerbera daisies are originally from South Africa so I'd assume they're not hardy in Zone 5 but as Justin C observed, it's possible yours self-seeded resulting in what might appear to be the re-emergence of last year's plant but which could be a new plant as a result of self-seeding. Smile, give thanks and enjoy it.

There have been several strains of hardier gerberas trialed In the UK, and, I presume, the US. Since yours is also in the rainshadow of a taller plant, I would not be jumping to conclusions that it is a seedling rather than the original plant - winter wet is more of a killer than the cold.

Try shasta daisies or cold tolerant painted daisies. there are daisies for our zone. we are Saratoga so not quite the same as you, but simi