Well, I guess it's too late but not really because it didn't get that cold... at least not where I am.

I would stay away from the heaters, instead use incandescent light fixtures. Lights make surprisingly good heaters. DO NOT use the clip on kind. They have a tendancy to fall off and break or worse, start a fire. It's better to take an old table top lamp without the shade and put it on the floor. I'd think one or two lamps with 60 watt fixtures should be enough.