Republican presidential candidate, Sen. Ted Cruz, R-Texas, looks to supporters as he speaks at a campaign stop at Waukesha County Exposition Center, April 4, 2016, in Waukesha, Wis.
Photo by Nam Y. Huh/AP

First Read: Catch-up day in Wisconsin

Updated

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.

It’s Catch-up Day in Wisconsin

The real storyline heading into today’s Wisconsin primary isn’t who will win – the polls have consistently found Ted Cruz and Bernie Sanders to be ahead, though we’ve already seen plenty of surprises this campaign season. Rather, it’s watching how big those wins will be, because both Cruz and Sanders are still trying to catch up to leaders Donald Trump and Hillary Clinton. And the way to catch up is to run up big margins to narrow the delegate score. Let’s start with the Republican race:

Trump holds a 275-delegate lead over Cruz

  • Trump 750 (47% of delegates won)
  • Cruz 481 (30%)
  • Rubio 172 (11%)
  • Kasich 143 (9%)

Trump must win 56% of remaining delegates to hit 1,237 magic number

Cruz must win 88% of remaining delegates to hit 1,237 magic number

Kasich must win 127% of remaining delegates to hit 1,237 magic number

Now if Cruz wins all of the state’s 42 delegates, which is possible if he runs the table, the percentage of remaining delegates that Trump will need to win to hit the magic number will increase to about 59%. If Cruz triumphs in Wisconsin, but Trump wins a handful of congressional districts, Trump’s percentage will be 57%. And if Trump somehow wins all of the state’s delegates, it will go down to 54%. So in a race where EVERY delegate matters, tonight’s margin – and the corresponding delegate haul – is what’s important.

Sanders needs a significant double-digit win to truly cut into Clinton’s delegate lead

As for the Democratic race, a narrow win for Bernie Sanders – as the current state polling suggests – won’t truly dent Clinton’s lead. What will, however, is a significant double-digit win in a state where 86 delegates are up for grabs tonight. Here are NBC’s updated delegate numbers on the Democratic side:

In pledged delegates, Clinton holds a 255-delegate lead over Sanders

  • Clinton 1235 (56% of delegates won)
  • Sanders 980 (44%)

In overall delegates (including superdelegates), Clinton holds a 680-delegate lead over Sanders

  • Clinton 1692 (63%)
  • Sanders 1012 (37%)

Clinton must win 34% of remaining delegates to hit 2383 magic number

Sanders must win 66% of remaining delegates to hit 2383 magic number

And keep this in mind

At this same time in 2008, Barack Obama’s pledged lead over Hillary Clinton fluctuated between 120 and 140 delegates – so Clinton’s current lead over Sanders is twice that, and it doesn’t include superdelegates. That’s the daunting math for Sanders. And it’s the math he needs to make up. Now it’s possible that wins for Sanders and Cruz give them momentum heading into the April 19 New York contest, but remember that Wisconsin (open primary, mostly white) isn’t New York (closed primary with diverse population).

Why Wisconsin isn’t your ordinary Midwest state

Finally, let us repeat something we wrote last week: Current momentum doesn’t necessarily explain why Cruz and Sanders are ahead in Wisconsin. Here’s what does explain it – there is maybe no other state in the country where the conservative and progressive movements are so well organized, thanks to the political battles there over the past five years. Think about it: On the GOP side, there is perhaps no more successful state Republican party than there is in Wisconsin. And the Democratic side, while it hasn’t been as successful in these political fights, is turbo-charged and unfraid when it comes to ideology. Polls close in Wisconsin at 9:00 pm ET.

RELATED: ‘Desperate times for democracy’ in Wisconsin

Is the GOP delegate system really corrupt, as Trump charged yesterday?

Campaigning in Wisconsin yesterday, NBC’s Ali Vitali reports, Trump lashed out at the GOP’s delegate process, calling it “corrupt.” Here’s what he said: “What kind of a system is this? So we’re dealing with a corrupt system, we’re dealing with a system that’s not fair.” But Republicans who have briefed NBC News on the delegate process push back that any of this is “corrupt,” as Trump alleges. As RNC Chair Reince Priebus said on “Meet the Press” last Sunday, delegates are the ones who SELECT the eventual nominee, and that has ALWAYS been the process, though the primaries and caucuses mostly influence whom these delegates ultimately select. The overwhelming majority of Republican delegates who will attend the GOP convention in July will be bound according to the primary/caucus results on at least the first ballot – no matter that delegate’s actual voting preferences. (The hitch, of course, is what might happen on a second or third ballot, as well as might happen on Rules committee votes, to which these delegates are unbound.) What Trump is acknowledging that he and his campaign perhaps aren’t built to withstand winning on a second or third ballot at the GOP convention – if he isn’t at the magic number of 1237 delegates. But that is not “corrupt.”

NBC|SurveyMonkey tracking poll

Trump, Clinton continue to lead their respective national races: Finally, here are the results from our weekly national NBC News|SurveyMonkey online tracking poll:

GOP race: Trump 45% (-3), Cruz 28% (+1), Kasich 18% (unchanged).

Dem race: Clinton 51% (+2), Sanders 42% (-1)

On the trail

Both Hillary Clinton and Bill Clinton campaign in New York… Bernie Sanders stumps in Wyoming… Ted Cruz is in Wisconsin. 

This article first appeared on NBCNews.com

Bernie Sanders, Donald Trump, Hillary Clinton, John Kasich, Ted Cruz and Wisconsin

First Read: Catch-up day in Wisconsin

Updated