OFF TO THE RACES: Delegates and momentum
Leading politics in the Journal Sentinel: "The election gives poll-leading Sen. Ted Cruz the opportunity to shift momentum away from real estate baron Donald Trump, who hopes to have Wisconsin cement his front-runner status and put him on a path to win enough delegates for the nomination outright. Ohio Gov. John Kasich is hoping to pick up some delegates as well. On the Democratic side, Sen. Bernie Sanders has led Wisconsin polls over former Secretary of State Hillary Clinton. He's looking for a chance to further boost his campaign, even though a win in Wisconsin may not give him many more delegates from the Badger State than Clinton."
From the New York Times: "As Mr. Cruz looks beyond Wisconsin, where he is favored to defeat Donald J. Trump on Tuesday, his frustrations with Mr. Kasich have increasingly been laid bare. With activists and operatives opposed to Mr. Trump fanning out across the electoral map in a scramble to deny him the nomination, Mr. Cruz's team has argued that it is Mr. Kasich's "quixotic" bid for the White House that will prove the biggest boon to Mr. Trump in the states to come."
From the Washington Post: "A loss for Trump in particular could reset a Republican contest that has been dominated by his outsider candidacy and outsize media presence. Amid scrutiny following several high-profile stumbles, state polls show Trump in a tight race with Sen. Ted Cruz of Texas, prompting speculation about whether Wisconsin could mark the beginning of the high-flying candidate's downfall."
A new Quinnipiac poll shows that 57 percent of all voters say America has "lost its identity," with almost eight in 10 Republicans agreeing and even more Trump supporters saying the same.
Our latest NBC News|SurveyMonkey poll shows a dip in Donald Trump's lead.
Clinton and Sanders have agreed to a debate in New York on April 14.
CRUZ: He's feeling confident in Wisconsin.
SANDERS: "Despite his steadily rising popularity, the president's expected role in 2016 as the Democratic Party unifier is on hold for another three-and-a-half months, if Sanders keeps his campaign going through the July convention," POLITICO notes.
TRUMP: "Donald Trump says he will force Mexico to pay for a border wall as president by threatening to cut off the flow of billions of dollars in payments that immigrants send home to the country, an idea that could decimate the Mexican economy and set up an unprecedented showdown between the United States and a key diplomatic lly. In a two-page memo to The Washington Post, Trump outlined for the first time how he would seek to force Mexico to pay for his 1,000-mile border fence, which Trump has made a cornerstone of his presidential campaign and which has been repeatedly scoffed at by current and former Mexican leaders."
POLITICO reports: "A POLITICO investigation revealed that Trump has assembled a privately funded security and intelligence force with a far wider reach than other campaigns' private security operations: tracking and rooting out protesters, patrolling campaign events and supplementing the Secret Service's protection of the billionaire real estate showman during his non-traditional campaign for the GOP presidential nomination."
His wife Melania told a crowd in Wisconsin "when you attack him he will punch back 10 times harder."
The New York Times observes: "Candidate spouses are often deployed as character witnesses, and the Trump operation believes that Melania Trump, 45, could help her husband as he has faced a barrage of unflattering news reports. She first made an appearance on the campaign trail in February in South Carolina, at a time when Mr. Trump was in need of some image softening amid criticism of his combative rhetoric."
*** Tuesday's "Andrea Mitchell Reports" line-up: On this Wisconsin primary day, NBC's Andrea Mitchell interviews: Clinton Campaign Press Secretary Brian Fallon; former RNC Chair Michael Steele; former RNC Communications Director Doug Heye; Bloomberg Politics' Mark Halperin and John Heilemann; the Washington Post's Chris Cillizza and Ruth Marcus; and our team of NBC reporters on the campaign trail.