Union shop stewert needs help?

Well i recently became shop Steward for union local 100 at the NEW GIANT STADIUM,to make a long story short DNC(DELAWARE NORTH CORP) are not respecting the union contract and are not respecting the seniority list, i have had meetings with the union president and still nothing is getting done .this is going on 3months, i really believe they are doing this on purpose to break up the union,so im thinking of writeing a letter to my senator for help, do you think she would help, what else can i do, the union seems to be weak on there spot,help