The next presidential election is expected to be a testing ground for a new generation of Republican leaders — senators who might include the charismatic Marco Rubio (Fla.), libertarian Rand Paul (Ky.) and tea party gladiator Ted Cruz (Tex.), and much-mentioned governors such as Chris Christie (N.J.), Bobby Jindal (La.), John Kasich (Ohio), Rick Snyder (Mich.), Scott Walker (Wis.) and Mike Pence (Ind.).

Then there is the potential for a parade of formers and also-rans. Former Texas governor Rick Perry is preparing for another race, a do-over after his 2012 debacle. Former Arkansas governor Mike Huckabee, who took the Iowa caucuses in 2008, has said he is thinking about it, too, as is former senator Rick Santorum (Pa.), who won Iowa in 2012…

Yet there is always the possibility that an ill-timed breakout moment could catapult one of the less-viable candidates to the nomination, said Republican consultant Mike Murphy, who mentioned Cruz as a potential “poison pill” in a general election.

“The Democrats had their McGovern,” Murphy said, referring to the 1972 landslide election. “Hopefully, we won’t have ours.”

That is why any real solution to the party’s problems lies in the candidates, many senior Republicans argue.