If they're LED DRLs, then there is a little basic relay you can buy on ebay for about $15 that you just wire to battery voltage, it sense when the car is running (voltage jump from alternator) and turns them on. Otherwise you can run a wire to the cigarette lighter as it's hot only when the ignition is on, but I personally hate crawling through the dash. If you go this latter route you need to put in a separate fuse near the lighter, just a 1A should be fine if they are LEDs.

Good luck.