Yes Electrical or Traffic Signal experience is required. And no, running RED Traffic lights do not count.
You do not need to be a licensed journeyman electrician, just have documentable experience. Check the web posting for all qualifications, just search for Colorado Dept. of Trans. job openings. I can't remember the address or I would link it.
Traffic Signal would be a big plus, since the job entails 80 percent Signal work and 20 percent Electrical work.
Good Luck.