They spent tens of millions of dollars, sent forth some of the heaviest of heavyweights in the GOP and the conservative movement to rail against him. They had tons of free media.

But in the end, the forces who had organized to stop Donald Trump's march to the nomination failed utterly. And now, with Trump's nearly insurmountable lead in delegates and the unlikely prospect that he can be stopped at the convention, many of the activists and moneymen who organized the effort appear to be prepared to accept Trump's nomination, if not embrace it.

Politico:

The talks about how to deal with Trump’s ascendance took on fresh urgency on Thursday. Some were intent on keeping up the fight. Prominent conservative activists gathered behind closed doors at the Army-Navy Club in downtown Washington, just a few blocks from the White House, to discuss how Trump could be defeated — even if it means waging a third-party campaign to run against him. The meeting drew around two dozen figures, including prominent activist Erick Erickson, conservative columnist Quin Hillyer, South Dakota businessman Bob Fischer and former George W. Bush adviser Bill Wichterman.

As attendees filtered out of the conference, one said they had agreed that Trump could still be stopped — and that they would do whatever was necessary to make it happen.

“The consensus was that we need a unity ticket of some sort, and we’ll let the candidates work out who the unity ticket is,” Hillyer told POLITICO, floating the possibility of an alliance between Texas Sen. Ted Cruz and Ohio Gov. John Kasich.

Others, however, appeared more resigned. At a posh resort in Palm Beach, Fla. — just minutes from Trump’s Mar-a-Lago estate — many of the Republican Party’s biggest donors discussed whether to continue shelling out millions on an anti-Trump offensive that so far has done little, if anything, to halt his rise. Many of those gathered, including New York hedge-fund manager Paul Singer and members of the Chicago Cubs-owning Ricketts family, have been the primary funders of Our Principles, a super PAC that spent heavily to defeat Trump, plastering Florida and other states with TV ads that portrayed him as a heartless businessman. Several of the donors reiterated their hope that Cruz or Kasich could still somehow win, sources familiar with the gathering told POLITICO. But others indicated they would be open to supporting Trump in the general election.

Some in the anti-Trump movement now concede that the push to defeat him hasn’t worked — and may be backfiring. In the final days leading up to the critical Florida primary, outside groups devoted to defeating Trump, including Our Principles PAC, spent more than $10 million against him only to see him notch a double-digit win and knock native son Marco Rubio out of the race.

This should be a lesson for all those liberal groups gearing up to protest Trump rallies and spend hundreds of millions of dollars attacking him in the fall.

There is no "there" there.  The fiercer the opposition to Trump, the more sympathy and support he recieves. Black Lives Matter and other protestors play directly into Trump's hands when they try to intimidate rally goers. Negative ads anger his supporters and give those who lean toward supporting him a reason to embrace him.

And even fact based ad campaigns that repeat some of the Donald's more odious and incendiary utterings don't generate outrage but rather admiration. He's "telling it like it is" - or something. 

With the left gearing up to conduct the most expensive, the most negative campaign for the last 150 years, they should look closely at the efforts made by conservatives to derail Trump's candidacy. For all the bombast and bluster against the candidate, the Trump phenomena only keeps growing.