While the prospect of routing Hillary Clinton and recapturing the White House brought out the true believers, it was Donald Trump's name on the ballot and his calls for economic patriotism, border security, and an end to imperial wars that brought out the throngs.
The crowds that continue to come out for his appearances and the vast audiences he has attracted to GOP debates testify to his drawing power.
Moreover, Trump has now been endorsed by Gov. Chris Christie, ex-chairman of the Republican Governors Association, and Sen. Jeff Sessions, one of the most respected conservatives on Capitol Hill.
Yet, with polls pointing to a possible Trump sweep on Super Tuesday, save Texas, his probable nomination, and a chance for the GOP to take it all in the fall, is causing some conservatives and Republicans to threaten to bolt, go third party, stay home, or even vote for Clinton.
They would prefer to lose to Clinton than win with Trump.
A conservative friend told this writer that Trump, unlike, say, Ted Cruz, has never shown an interest in the Supreme Court, which, with Justice Antonin Scalia's seat vacant, hangs in the balance.
Yet, surely, a President Trump, hearing the clamor of those who elected him to find a Scalia, would be responsive.
With President Clinton, the court is gone for a generation.
We hear wails that the nomination of Trump would mean the end of the conservative movement. But how so?
If Trump won and conducted a conservative government, it would validate the movement. If Trump won and turned left, it would inspire an insurgency like Ronald Reagan's in 1976, when the Ford-Rockefeller-Kissinger administration moved too far toward detente.
If Trump ran and lost, the conservative movement would have President Clinton to unite and rally the troops against.
One recalls Barry Goldwater's historic wipeout in 1964. But, in 1966, Republicans made the greatest gains in a generation, and went on to win the presidency for 20 of the next 24 years.
Undeniably, a Trump presidency would mean an end to the Bush and establishment policies on trade, immigration and intervention.
But those policies have already been repudiated in the primaries, as they have proven to be transparent failures for America.
As long ago as the early 1990s, populist conservatives were imploring George H. W. Bush to secure our Mexican border, as tens of thousands poured across in the San Diego-Tijuana corridor. Gov. Pete Wilson turned near-certain defeat into a stunning comeback victory in 1994 by promising to send the National Guard.
Why did the establishment not respond then to the electorate? Why, instead of trashing Wilson for imperiling future party prospects with Hispanics, did the establishment not do what the people had demanded and move decisively to secure our southern border?
What is conservative about uncontrolled borders?
Why, as trade deficits with China and the world rose from the tens of billions to hundreds of billions, did the establishment not wake up and see the shuttering factories, the lost jobs and the ghost towns arising across America -- and react?
Could they not see that, as we celebrated globalization, Beijing and Tokyo were practicing ruthless mercantilism and protectionism?
At the end of the Cold War in 1991, many Americans urged that, with the Soviet Empire dissolved and Soviet Union disintegrating, it was time to bring our troops home and let the rich fat nations that had been freeloading for half a century provide the soldiers and pay the cost of their own security.
Instead, the establishment opted for empire, for expanding old alliances, dumping over regimes, crusading for democracy, sending our soldiers out to remake Third World countries in the image of Iowa and Vermont.
Who now thinks all these wars were worth the cost?
Whether Trump wins or loses the nomination, the immigration, trade and foreign policies pursued by the elites since the end of the Cold War are dead letters. The nation has declared them to be so in the primaries.
Who is campaigning, in either party today, for open borders, or passing The Trans-Pacific Partnership, or sending troops back to Iraq or into Syria?
The Bernie Sanders insurgency appears to have been turned back by the vested interests of his party. But like the George McGovern insurgency in '72, which also relied heavily upon the enthusiasm of the young, Sanders' socialism may be the ideological future of his party.
The same may be said of the Trump insurgency. Whatever happens at Cleveland, the returns from the primaries look like the passing of the old order, the death rattle of an establishment fighting for its life, and being laughed at and mocked as it goes down.
As in 1964 and 1980, a new Republican Party is taking shape.
Defections are to be expected, and not altogether unwelcome.