yeah that's technically enough light, i think halogen is the wrong spectrum of light though.
the thing about lights is this.
there are 3 types of lights that you can use to grow bud. period.
these are the only three that are effective:
#1 High-Pressure Sodium (the bright ass orange streetlights, it's good for the flowering stage of the plant and puts out the most light per watt)
#2 Metal Halide (bright ass white street lights, good for vegetative growth, i.e. for and indoor grower the first 4 weeks)
#3 Fluorescent (good for vegetative growth, can be used for flowering but with lower yields, not as hot as the other lights, and you can get Compact fluorescents that screw in a regular light socket for super cheap, you know the little spiral ones)
everything else has been tried, and yes it will keep a plant alive and a plant will even grow, in fact it will grow VERY TALL and skinny because it will be thirsty for light and reaching for the heavens to find some, and in the end those halogens are so hot they will burn your plants at a range close enough to grow them.
you can get a 150w HPS for 20 bucks here:
http://www.e-conolight.com/Product/EProductDetail.asp?ProductFamilyID=7&FGNumber=E-MT6H151G
but for the next week while you are getting your new light yes they will keep your seedlings alive, just check the temperatures under the lights make sure it's under 85 degrees.
oh and miracle grow is too hot (ie. too strong) for cannabis, don't give them any fertilizer for 3 weeks after they sprout, also the 7 you have in one bucket need to be in separate containers, you can just use plastic cups with a hole cut in the bottom they work fine.