republicans democrats battle dozen u.s. state hold elections governor tuesday many race could close call draw national attention debate transgender right republican governor pat mccrory seek second term roy cooper democrat state attorney general since 2001. poll show cooper modest lead state also competitive race president u.s. senate one year close gubernatorial race poll put republican former navy seal eric greitens dead heat democrat chris koster state attorney general bid succeed governor jay nixon democrat serve maximum two term office indiana governor mike pence initially seek re-election withdraw gubernatorial race july campaign republican presidential nominee donald trump run mate lieutenant governor eric holcomb republican step pence compete democrat john gregg former state lawmaker gregg narrowly lead holcomb accord poll democratic businessman jim justice lead republican state senate president bill cole poll though data sparse democratic governor earl ray tomblin bar term limit run democratic governor steve bullock battle republican tech entrepreneur greg gianforte keep seat poll conduct last month mason-dixon poll research put bullock ahead gianforte 47 percent 45 percent democrat colin van ostern modest lead republican chris sununu recent poll members state executive council help administer state government seek succeed democratic governor maggie hassan run u.s. senate term two years republican lieutenant governor phil scott democrat sue minter former state transportation secretary vie succeed retire governor peter shumlin democrat one poll last month give scott seven-point lead another show dead heat term two years democratic governor kate brown favor republican bud pierce oncologist brown swear last year predecessor john kitzhaber resign scandal election final two years kitzhaber term poll put incumbent governor gary herbert republican advantage democrat mike weinholtz healthcare executive utah herbert take office 2009 predecessor jon huntsman resign seek second full term democratic governor jay inslee widely favor poll win second term republican bill bryant businessman former commissioner port seattle republican doug burgum former microsoft corp executive expect defeat democratic state representative marvin nelson solid republican state north dakota governor jack dalrymple republican eligible run re-election 2016 decline seek another term democrat john carney member u.s. house representatives wide lead university delware poll last month republican colin bonini state senator democratic governor jack markell prohibit term limit run re-election position hold since 2009. factbox governorships grab 12 state