But to get a Republican in the White House, the GOP needs to nominate a candidate favored by the grassroots. Too narrow? Well, trends in survey research show that anti-establishment sentiment is intense among GOP grassroots voters -- and not going away. Very simply -- and this is the hard reality -- the grassroots -- or a big portion -- aren’t going to turn out to vote for an establishment Republican (short of an existing or looming crisis).

Here’s the dilemma -- and it’s a big one. Electing a Democrat president in 2016 would be bad for the nation, very bad. Conservatives agree. Establishment Republicans do too, in important regards, at least. To avert further troubles domestically and dangers overseas, the Mayflower truck that unloads stuff at the White House in January 2017 needs to be for a Republican.

This from Craig Robinson, who runs TheIowaRepublican.com. From a report in the Centre Daily Times dated September 1:

Robinson found “the establishment is toxic,” and noted that in the Register poll, candidates who have never held public office, Trump, Carson and former business executive Carly Fiorina, totaled 46 percent. Jeb Bush, the former governor of Florida; Sen. Marco Rubio, R-Fla., and John Kasich, the governor of Ohio, totaled 14 percent.

Robinson pointed out that Iowa is a caucus state, meaning that turnout operations are critical. Organization is a big part of the Iowa ball game, and that gives Jeb or others a chance to upset expectations. Or not. Trump, most notably, is working there.

Per CNN, Trump is “organizing, organizing, organizing.” From an August 31 CNN report:

One sign the campaign is serious about their strategy in the Hawkeye State: The Trump campaign hired top Iowa strategist Sam Clovis, once proclaimed as a "conservative icon," away from the Perry campaign. Clovis, who was Rick Perry's Iowa co-chairman, will serve as national co-chair and senior policy adviser.

Trump or no Trump, the grassroots rebellion isn’t disappearing. The intensity of distrust for the establishment by the grassroots makes bridging differences improbable -- that is, in ways beneficial to an establishment nominee.

From the Washington Post’s feature “The Fix,” dated August 31:

1. Republicans want an outsider; Democrats don't The poll finds 77 percent of Democrats would prefer a candidate with experience working the halls of Washington, D.C. On the GOP side, 73 percent prefer someone who is a D.C. outsider. These numbers seem clearly reflective of the fields of primary candidates that exist. Democrats' top two contenders are clear D.C. insiders, which is probably why their party feels that way. But with the GOP, their field does have some insiders too, and yet three-fourths want an outsider. It's a big reason Trump and Ben Carson are leading and Carly Fiorina is ascendant. It's also why candidates who have served in Congress are taking just one out of every five votes in the new Iowa caucus poll released over the weekend.

Grassroots alienation, in no small part, cost Romney the presidency in 2012. Nearly three years later, the abysmal and distrust-inspiring performance by congressional Republicans has caused that alienation to widen.

The GOP establishment isn’t going to hand the nomination to a grassroots’ preferred candidate, of course. The establishment didn’t step aside for Goldwater or Reagan. It has deeply vested interests in nominating one of its own. The grassroots is going to have to fight for an acceptable candidate. Sooner rather than later, grassroots leaders need to huddle to agree on a plan to unite around a candidate. Doing otherwise invites a repeat of 2012, when Romney rode primary pluralities to the nomination against a fractured conservative field.

Trump’s candidacy is the wild card. He’s proving to be the Great Disruptor. Trump has shown remarkable consistency in topping national horserace polls and surveys in early state nominating contests.

If Trump rolls up majorities or larger pluralities in the early going, the GOP field will winnow out, as fundraising dries up and pros and volunteers head for the exits. (Rick Perry and the Scott Walker are already history, thanks in large measure to the Trump factor.)

Smaller plurality victories for Trump are problematic (provided victories come). Enough candidates may be close enough to Trump’s totals to soldier on. (Don’t expect a big batch of candidates to follow Walker’s advice about immediately leaving the race to better takedown Trump. They all have their reasons for staying in. Others haven’t tanked as dramatically as Walker.)

In any event, expect Jeb, Rubio, or Kasich capturing a quarter to third of the establishment-identifying GOP.

Would conservative candidates combine with Trump to push him over the top? Other than Cruz – who’s more a “maybe” – it’s hard to say. Would Trump support a conservative? There’s a strong likelihood of Jeb, Rubio, and Kasich hammering out a deal.

That’s why grassroots leaders need to be working now to secure a general understanding among non-establishment candidates. Getting candidates to unite at a critical juncture, and getting the grassroots to agree, is a lot like herding cats, you say? It’s a tough challenge and the goal may prove elusive, but the effort is indispensible. The grassroots will need to galvanize or risk opening the door to the establishment again in 2016.

If an establishment Republican wins the party’s presidential nomination, the likeliest scenario is a depressed turnout among grassroots voters, perhaps more significantly than 2012. That could negatively impact down-ballot races (that’s congressional, state, and local).

Like the establishment’s refrain about Obama in 2012, the argument now is that the grassroots will rally to oppose Hillary, Biden, or Sanders (however improbable Bernie is). If that reasoning were true, then Romney should be seeking his second term.

Should the grassroots secure the nomination for a preferred candidate, it needs to find ways to fold the establishment into a coalition. That notion is cringeworthy for many grassroots activists. But Reagan did so expertly in 1980. Trump, who’s the master of the “art of the deal,” would attempt to woo establishment leaders into backing him.

Whether its Hillary, Joe, or Bernie, the Democrat must be defeated next year. But to win this time, victory must come from the grassroots up.