Almost half a year later, the postmortems continue. After an election in which Republicans failed to capture the White House and lost several seemingly winnable Senate seats, in which their tenuous majority in the House was retained more by way of redistricting than by the will of the voting public, everyone within and without the G.O.P. agrees it has a big problem.

Some insist that the critical failure of 2012 was one of messaging, that the party will return to power not by changing its beliefs but by finding the right tone — and the right candidate — to articulate its…