In light of the GOP internal struggle it is interesting to look at President James A Garfield who was elected as  a direct consequence of a divisive and fractured convention.  Garfield said the following, and his words are as pertinent today as they were in 1880:

Now, more than ever before, the people are responsible for the character of their Congress.  If that body be ignorant, reckless, and corrupt, it is because the people tolerate ignorance, recklessness and corruption.   If it be intelligent, brave, and pure, it is because the people demand these high qualities to represent them in the national legislature…
If the next centennial does not find us a great nation… it will be because those who represent the enterprise, the culture, and the morality of the nation do not aid in controlling the political forces.

The Ohio legislature had just chosen Garfield in 1879 for the U.S. Senate seat when a faint movement began for Garfield as the next Republican nominee for President to succeed Hayes – he had chosen not to stand for re-election.   In early 1880 Garfield endorsed John Sherman for the party’s Presidential nomination in exchange for Sherman’s earlier support of Garfield for the Senate. However, at the outset of the Republican convention, a deadlock ensued between supporters of former President Grant, James G. Blaine, and Sherman; the delegates began to look to Garfield as an optimal compromise choice.
Garfield eloquently defended dissenting West Virginia delegates in his speech against Sen. Conkling’s convention rule that stated all state delegates must vote unanimously for only one candidate.   After over thirty ballots, the vote totals for the leading contenders were within five votes of where they had been on the first ballot. With the 34th ballot, Wisconsin began the break to Garfield that would end with his nomination as the party’s Presidential candidate.
Garfield’s capture of the 1880 nomination for the Presidency over the prominent contenders was considered historic.  Garfield defeated the front-runner Ulysses S. Grant’s controversial third term bid for the nomination.
He was assassinated in office at the age of 49 –  More