First Read is a morning briefing from Meet the Press and the NBC Political Unit on the day's most important political stories and why they matter.

I Would Die 4 U – Or Maybe Not

Things can always change in American politics, but maybe the biggest story in politics over the past two weeks has been how the “Stop Trump” forces are in retreat -- and part of it has been their own doing. Indeed, we can point to four reasons why #NeverTrump is struggling. One, the party is going out of its way to emphasize that it isn’t changing the convention rules.

Case in point was yesterday at the Republican National Committee meeting in Florida, where the RNC’s Rules Committee beat back any changes to how the GOP will conduct its convention in July. “The idea that you would replace the entire operating manual…could only be viewed by any one candidate as an attempt to favor another candidate, and that’s extremely dangerous,” warned Georgia Committeeman Randy Evans, per NBC’s Alex Jaffe. If the party is already worried about perceptions given Trump’s message against rigging the game, what will the political world look like three months from now when the stakes are even higher? The party already looks like it’s been beaten in submission.

Cream(ed) over the airwaves

Two, Stop Trump isn’t putting its money where its mouth is. After spending some $2 million to defeat Trump in Wisconsin earlier this month, the outside groups airing ads against the real-estate mogul didn’t spend a single cent on TV in New York (though they did shell out money in digital ads), and they’ve spent just $19,000 so far in next week’s contests (just in Maryland). Now the Club for Growth is up with a $1.4 million ad buy in Indiana. But ask yourself: If the message that Trump is wholly unacceptable to be the party’s nominee, why aren’t these groups fighting Trump everywhere? Indiana looks to be a real battleground in two weeks. But does the political needle move in Trump’s direction after running off six-consecutive wins? We’ll see. Here are our ad-spending numbers:

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I guess I should of known/By the way you parked your car sideways/That it wouldn’t last

A third reason why #NeverTrump seems to be in retreat is that there still isn’t a clear anti-Trump alternative, especially after Ted Cruz finished third in New York, and as John Kasich doesn’t look like he’s leaving this race. Bottom line: It is very hard to organize around a negative; voters want to vote for something.

U Got the Look

And the fourth and final reason why anti-Trump forces seem to be in retreat -- at least for now -- is that Trump appears to be a much more disciplined campaigner. Remember, Mitt Romney and anti-Trump forces started to flex their muscles after Trump’s KKK/David Duke comments. Well, while Trump continues to make news and controversy, it is much less than it used to be. Question: Does a more disciplined Trump take the wind out of Stop Trump’s sails? That said, Trump fired up conservative critics after he sounded much more moderate on abortion, taxes, and North Carolina’s anti-LBGT law during yesterday’s “Today” town hall. Look, we get how American politics is full of ebbs and flows -- Trump appeared strong after his March 15 wins, he appeared much weaker after a string of defeats, and he appears strong again right now. So don’t count out #NeverTrump. But right now, it sure seems to be in retreat. Here’s the GOP delegate math:

Trump holds a 286-delegate lead over Cruz

Trump needs to win 57% of remaining delegates to reach 1,237 magic number

Cruz needs to win 98% of remaining delegates to reach 1,237 magic number

Kasich needs to win 158% of remaining delegates to reach 1,237 magic number

This is what it sounds like when doves cry

In an exclusive interview with NBC’s Andrea Mitchell, presidential candidate Bernie Sanders admitted that it’s going to be difficult to win if he doesn’t have a majority in pledged delegates. “Look, if we do not have a majority, it's gonna be hard for us to win,” he said. “The only fact that I think remains uncertain is if we continue to be running significantly stronger than she is against Donald Trump, or whoever the Republican nominee will be. I think that's a factor.” Translation: Sanders isn’t going to take his fight into the convention if he’s trailing Clinton. And here’s the reality: He’s trailing Clinton by 200-plus pledged delegates – twice as much as Clinton ever trailed Barack Obama in 2008. The numbers:

In pledged delegates, Clinton currently holds a lead of 272 delegates with Washington delegates to still be allocated

Clinton 1,423 (55%)

Sanders 1,151 (45%)

Clinton must win 41% of remaining pledged delegates to get a majority in pledged delegates

Sanders must win 59% of remaining pledged delegates to get a majority in pledged delegates

In overall delegates (pledged + super), Clinton holds an overall lead of 696 delegates

Clinton must win 29% of remaining delegates to reach 2,383 magic number

Sanders must win 71% of remaining delegates to reach 2,383 magic number

Let’s Go Crazy

But as MSNBC’s Alex Seitz-Wald and NBC’s Shaquille Brewster observed, Sanders criticized Clinton – after seeming back away earlier in the day. “In his first campaign appearance since a crucial loss in New York’s primary, Bernie Sanders on Thursday dialed back his rhetoric on Hillary Clinton – only to ramp it back up later in the day… Just a few hours later, at a rally in Reading, Pennsylvania, rhetoric on Clinton’s transcripts and super PACs were back. ‘When I talk about difference between Secretary Clinton and myself, one of the major differences is precisely how we raise money for our campaigns,’ Sanders said. He noted Clinton has ‘several super PACs’ that take money from Wall Street, and suggested that she herself ‘represent[s] Wall Street’ and ‘the billionaire class.’” More: “‘In addition to that, as you know, Secretary Clinton has given speeches on Wall Street for $225,000 a speech. Not a bad day’s work,’ he said, winding the crowd up for what has reliably become one of his best applause lines.”

On the trail

Hillary Clinton spends her day in Pennsylvania, hitting Jenkintown, Pittsburgh, and Scranton… Bernie Sanders is also in the Keystone State, campaigning in Philly, Gettysburg, and Millersville… Donald Trump stumps in Delaware… Ted Cruz is also in Pennsylvania… And John Kasich campaigns in Connecticut.