None of them had a niche.
Graham - How many Republican primary voters do you think base their vote on being a hawk, and of those, how many do you think would be okay with "Grahamnesty?"
Huckabee - Old news, his pandering style was very dated
Santorum - Old news, only got traction in 2012 because he was at the right place at the right time to be flavor of the month against Romney, someone who many Republican primary voters disliked
Perry - Old news, literally a joke candidate best known for forgetting which agency of government he'd abolish
Jindal - Brought nothing to the table, and his name is literally "Piyush Jindal." Need I say more?
Jindal was also so unpopular that his successor in LOUISIANA was a Democrat. Also, he, Huckabee, Santorum, and Perry were competing for basically the same shrinking slice of the Republican Electorate, hardcore SoCons, and Carson and Cruz cornered that market, with a large number also going for Trump.
