Looking for a recommendation for a video camera that has good low-light capability.
Budget is $300-600 or so.

Vince -
I think you're not getting responses because you're asking a lot for $300-600...

What use are you contemplating, and which things are the priority? Is used an option, and does it have to be a video camera, or would a still cam that shoots decent video be an option? And the ultimate indefinite qualifier, how "low" are we talking...

There are some cheap but passable options, but they don't qualify as "enthusiast" cameras in mid-consumer price ranges.

Let me qualify that and say "better" low light. Is any one cam known for low light

Really depends on what you want to do,
but my Nikon D5300 is about twice as good as any DX DSLR.
It will shoot decent 1080 P60 Video at 12,800 ISO

Completely off the wall suggestion, Sony DSC-RX100Mk2 shoots decent video and is a handy camera for other purposes. Limited zoom range (though clear zoom is very usable), 29 minute clip limit, and at the higher end of your range, but it does come under the "enthusiast" category, with full manual capability. And how many video cams fit in your pocket when needed!? Low light is decent considering.

Much depends on what you want to use the camera for... and whether a used camera (thus cheaper, and more budget friendly) is an option. There have been some very fine cameras over the last few years that might fit the bill, depending on intended use.

I've had good luck with my Canon EOS M, useable video all the way to the top of the ISO range, and meets your budget.

And the two Canon EOS M lenses are fantastic!