With Donald Trump heading toward what more and more Republicans believe will be victory in the GOP primaries, an increasing number of party figures — none fans of Trump originally — are making their peace with the idea of Trump as their nominee. Some are even working out an argument, at least in their own minds, that Trump has a plausible chance to defeat Hillary Clinton in a general election.

There have been brief establishment flirtations with Trump in the past. But those flirtations ended when Trump said something outrageous or the campaign took some (brief) anti-Trump turn, most recently when Ted Cruz won the Wisconsin primary on April 5. Now, with Trump's five-for-five victories in the Northeast last Tuesday, some establishment members are doing more than flirting with the idea of Trump. They're accepting it.

What follows won't include names, but is based on private conversations with several stalwart Republicans, including a former top party official, former members of Congress who have been active in the campaign, a member of the party's foreign-policy establishment, two former managers of GOP presidential campaigns, and more. In addition, several other influential Republicans, like Sens. Bob Corker and John Cornyn, along with former House Speaker John Boehner, have spoken out publicly in a somewhat Trump-friendly way recently.

Each says different things, but overall, there is one reason for the change in attitude: voters. In this case, 10,056,690 Republican primary votes for Trump (so far) have a way of changing a politician's mind.

The GOP politicos carefully count delegates — some the old-fashioned way, on a legal pad, instead of using the various delegate calculators on the web — and now believe Trump will win at least the 1,237 required to clinch the Republican nomination on the first ballot. Most began to feel that way after Trump won New York with 60.5 percent of the vote, not only stopping the momentum Cruz had gained by winning Wisconsin but also punching a hole in the idea of a Trump "ceiling."

"They are recognizing that the voters are speaking," said one GOP veteran of his establishment colleagues.

Because of that, the insiders dismiss continuing efforts to stop Trump as too little, too late. In hindsight, they now say that was true all along. The millions spent on ads against Trump in Florida? Too late. National Review's "Against Trump" broadside? Too late. #NeverTrump? Too late. For whatever reason, the GOP politicos have concluded, anti-Trump forces in the party were always behind the times, to Trump's benefit.

The insiders also know other Republicans think the same thing. They took notice recently when Republican National Committee members held a meeting in Hollywood, Fla. At that meeting, member after member said that he or she would support Trump if Trump is the party's nominee. Now, Republican National Committee members pledging to support the Republican nominee should be no surprise. But it was an institutional confirmation that the party will accept Trump.

Perhaps most importantly, some have begun to game out a Trump vs. Clinton general election contest. They know that dozens of polls have shown Clinton trouncing Trump, often by double digits. But they were struck by a recent George Washington University Battleground Poll that showed Clinton winning by just 3 points. It's just one poll, but for some it confirmed the idea that there might be a different dynamic at work in the race once Trump becomes the nominee and the contest is simply Donald vs. Hillary. The fight will become more even.

"Trump does bring a little magic to this in that he could shuffle the traditional battleground map," one former presidential campaign manager told me. "I haven't seen any data on that, but I'm just getting a feeling that he's going to put a couple of Midwestern states in play."

"I saw Goeas' poll this week," the former manager continued, referring to Ed Goeas, the Republican author of the Battleground Poll. "Look, Trump hasn't even started to take out Hillary yet. He hasn't even begun taking it to her, and when he does, it's a two-prong thing. One, it unites the party like no other thing, and two, it will start to damage her. Look at what he's done to Lyin' Ted and Little Marco and Low Energy Jeb."

Maybe the insiders are deluding themselves. The RealClearPolitics compilation of general election head-to-head polls is a long list of blue numbers favoring Clinton. But the fact is, some influential Republicans are beginning to question the assumption that Trump is guaranteed to lose big.

That's the kind of change that decisive primary victories produce. Add to that the belief that Trump's only remaining GOP rival, Cruz, is too unlikeable to win the White House. "The memories of Trump's last outrageous statements have faded a little bit and he's won big," said another insider. "I think that Boehner obviously put it in pretty blunt language ["Lucifer in the flesh"], but he kind of reflected what the so-called establishment feels. They think they might be able to get along with Trump but remember that they can't get along with Cruz."

None of this means party insiders are enthusiastic about Trump. As one less optimistic type told me, they are trying to figure out whether to try to help Trump in a general election race or sit out the campaign in a deep funk. But the bottom line is, they can read election results. They realize the voters are telling them something. And they are moving toward accepting Trump as their nominee. "If anything," said another insider, "it may be happening faster than you think."