First, the fact that Trump’s team of law­yers is fix­ated on se­cur­ing bal­lot ac­cess for next spring’s primary con­tests – all 56 of them, in­clud­ing the five ter­rit­or­ies and Dis­trict of Columbia – means that he’s not spend­ing that ef­fort to lay the ground­work needed to run as a third-party can­did­ate. Trump can ill af­ford to waste time if he in­tends on qual­i­fy­ing for the Novem­ber bal­lot as an in­de­pend­ent, which, party of­fi­cials es­tim­ate, would re­quire some­where close to $10 mil­lion to gath­er more than half-a-mil­lion sig­na­tures ne­ces­sary to qual­i­fy across 51 jur­is­dic­tions.

Secondly, in many states, a third-party run only be­comes more dif­fi­cult for can­did­ates who’ve already par­ti­cip­ated in one of the ma­jor party’s primar­ies.

The South Car­o­lina fil­ing lan­guage demon­strates the dif­fi­culty Trump could face in qual­i­fy­ing as a third-party can­did­ate after a Re­pub­lic­an primary run. If Trump com­petes in the GOP nom­in­at­ing sea­son but doesn’t win the nom­in­a­tion, some states with “sore loser” laws – like Ohio – will de­clare him in­eligible for the gen­er­al elec­tion bal­lot. Oth­ers, such as South Car­o­lina, don’t have laws on the books, but their state parties are ex­per­i­ment­ing with new ways to en­force loy­alty.

In ef­fect, these dy­nam­ics con­verge to provide in­cent­ive for any­one con­sid­er­ing a third-party can­did­acy to make their de­cision well be­fore primary sea­son be­gins.