small speaker wire can handle about 45-75 watts. if you're gonna be using a 200 watt amp, id suggest using 8 or 12 gauge wire. for 2 reasons,
1. it will bring more power to the speakers thus sounding better
2. it will be easier to wire than using stock speaker wires

96 Contour GL I4
Nothing Done except for audio
Sony Head unit--replacing in the near future
2 12" MTX 6000's
Optimus 400w amp--good ol' radio shack
5x7 kenwoods rear door--upgrading speakers this summer
Strobe lights in the grill
adding undercarriage lights soon