Donald Trump's victory in Indiana seems to have completed the billionaire's hostile takeover of the Republican presidential nomination, but has left the conservative party badly split.
Centre-right Republicans came out of Mitt Romney's 2012 presidential election loss to Barack Obama searching for answers, with a post-mortem by party officials concluding that more needed to be done to reach out to women and minorities, who make up an increasing share of the electorate.
But over the next four years, as in-fighting in Washington and dissatisfaction with Obama increased, voters seem to have come to a different conclusion, blaming party leaders and politicians.
Enter Donald Trump. He may have been seen as a hopelessly unconventional candidate, but he was able to tap into populist anger that most in the party leadership seemed to have no idea existed.
Trump is far from a hero to many Republicans, however. In fact, many of the party's grassroots conservatives, long-time activists and pundits have declared they would never support the billionaire real estate mogul. Using the Twitter hashtag #NeverTrump, they point to his shifting policy stances as evidence he does not actually share their conservative positions and call him unfit to hold the nation's highest office.
Romney even made forceful calls in a speech earlier this year urging his party not to nominate Trump.
Trump was so disliked by many within the party that they had lately rallied to opponent Ted Cruz, who had himself made many enemies within the party establishment.
Cruz ended his presidential bid late Tuesday after it became clear his attempt to keep Trump shy of the delegates needed to secure the nomination would fail and with it hopes that delegates would name an alternate candidate.
In withdrawing from the race, Cruz did not mention Trump or the need to rally behind the nominee. Instead he spoke of carrying forward conservative principles despite the setback.
"Will we rise to meet the challenges that face our nation on the international stage or will we withdraw and cower timidly from the world?" Cruz asked as he listed issues from fighting terrorism to creating jobs and battling political correctness.
"This is the responsibility with which we have been charged by history. This is our challenge. This is the fight that falls to our generation."
It remains unclear whether Cruz will eventually be persuaded to support Trump, but other vocal opponents of the New Yorker appeared unlikely to shift position.
Nebraska Senator Ben Sasse declared that Indiana's results did not change his opposition to Trump, while Senator Lindsey Graham, who also briefly ran for president, tweeted Tuesday, "If we nominate Trump, we will get destroyed ... and we will deserve it."
Prominent conservative commentator Bill Kristol declared he would seek a third-party alternative to Trump or Clinton.
While a group organized to advocate against Trump said it would continue to oppose his nomination and "draw a line between him and the values of the conservative cause," Republican National Committee chairman Reince Preibus called on the party to unite behind the "presumptive nominee."
Preibus' remarks focus on the one thing that could potentially draw Republicans together in support of Trump: intense dislike for Democrat Hillary Clinton.
With many in the media anticipating a "Trumpocalypse" for the Republicans, Trump seemed unworried about his party's unity. Without naming names, he declared in his victory speech that many Republicans who had once opposed him were now calling to court him.
"We want to bring unity to the Republican Party. We have to bring unity," said Trump, who maintains he can put traditionally Democratic states in play in November elections.
Former rivals in the presidential race Chris Christie and Ben Carson have vocally supported Trump, and other lawmakers have lined up in recent days.
A speech on foreign policy in Washington last month and meetings with party officials seemed designed to smooth over fears within the party's highest ranks.
Speaker of the House Paul Ryan, the top Republican in Congress, has repeatedly sought to distance himself from the frontrunner.
Ryan must guard against what some Republicans fear. With Trump leading the way in November elections, other Republican candidates in Congress and local races could be damaged and the party could even lose control of the Senate and the House of Representatives.
Ryan himself has previously said he does not hope to be chosen as an alternative to Trump, however, leaving his party with even fewer options to weather the coming storm.