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.

Trump’s Temperament Problem

For all of the attention on Hillary Clinton’s honesty and trustworthiness, Donald Trump has maybe even a bigger problem – temperament. According to the April NBC/WSJ poll, only 19% of all registered voters gave Clinton good marks for being honest and straightforward, while 48% gave her a “very poor” rating on this attribute. But Trump’s numbers on whether he has the right temperament to be president were even worse in the poll: Just 12% gave him high marks here, versus 60% who gave him a “very poor” score. And Trump’s temperament – of lack thereof – was on fully display at his news conference yesterday.

Now this kind of language has made Trump an endearing figure to his supporters. And bashing the media only helps Trump. But you have to ask: Is this how Trump would govern as president? Fellow journalists, don’t focus too much on the attacks on the media. Focus instead on Trump criticizing (again) a federal judge and his party. Those issues go at the heart of governing and respecting the nation’s system of checks and balances.

How Trump University sold the brand

Speaking of the judge in the Trump University case, he unsealed documents yesterday that became news. NBC’s Alex Jaffe: “Trump University salespeople were instructed to play to peoples’ emotions and suggest that potential customers rely heavily on credit card debt or retirement funds to pay for the classes, according to documents unsealed by a federal judge Tuesday. ‘You don’t sell products, benefits or solutions — you sell feelings,’ Trump University salespeople were counseled. Another document related to a lawsuit against the for-profit university advises: ‘This sales process is based on managing the emotions of the client by focusing on the psychology of the sale. The metaphor we use for this process is the Roller Coaster of emotions.’ Those marked just a portion of the tips and tricks outlined in the Trump University “playbooks,” manuals that comprised the bulk of the nearly 400 pages released by Southern California District Judge Gonzalo Curiel’s order.”

Penn, Garin: Hillary needs to fix her positives

In Politico, Clinton’s 2008 chief strategist says that Hillary needs to focus more on her positives rather than attacking Trump. “From her point of view, establishing positives is far more important to winning,” said Penn. “Why spend so much energy attacking Trump, what difference does it make, when he’s over 57 percent negative and she has a lot of leadership qualities that have gone unsung? It’s like beating a dead horse.” Added Garin, another key member of her ‘08 campaign team: “There would be a real benefit in building her positive case.”

Bernie’s rhetorical sleight of hand on superdelegates

But one impediment to Clinton fixing her positives – at least right now – is the still-ongoing Democratic race versus Bernie Sanders. Yesterday while campaigning in California, Sanders said it will be “factually incorrect” that Clinton will clinch the Dem nomination on June 7 because she won’t have a majority of “real delegates,” per the Washington Post’s Dave Weigel. But as the New York Times’ Nate Cohn points out, “Sanders needs superdelegates to exist to have a chance of vetoing voters, but he also needs their preferences not to count to survive.” Bottom line: Sanders is moving the goal posts here. In 2008, Barack Obama clinched the Democratic nomination through a combination of pledged delegates and superdelegates. After all, a majority of ALL delegates is 2,383 (out of 4,765), while a majority of pledged delegates is 2,026 (out of 4,051). Here’s the updated Dem delegate count:

In pledged delegates, Clinton currently holds a lead of 270 delegates

Clinton 1,770 (54%)

Sanders 1,500 (46%)

Clinton must win 33% of remaining pledged delegates to get a majority in pledged delegates

Sanders must win 67% of remaining pledged delegates to get a majority in pledged delegates

In overall delegates (pledged + super), Clinton holds an overall lead of 770 delegates

Clinton must win 8% of remaining delegates to reach 2,383 magic number

Sanders must win 92% of remaining delegates to reach 2,383 magic number

New NBC/WSJ/Marist poll of California out later today

Staying with the Clinton-vs.-Sanders race, we’ll be releasing a new NBC/WSJ/Marist poll of California later this afternoon.

Obama returns to Elkhart, IN

At 3:25 pm ET, President Obama delivers remarks in Elkhart, IN – which he visited early in his presidency to sell his economic stimulus. Elkhart’s unemployment rate in 2009 was nearly 20%; now it’s around 4%. The Indianapolis Star has more: “Yet, as the president celebrates Elkhart’s recovery, some of the city’s business leaders are anxious about what they see as the same problem they faced eight years ago: a fragile economy dependent on fickle recreational vehicle sales.Obama is slated to hold a town hall at the Lerner Theatre and deliver a speech at Concord High School, the same site he visited in January 2009 during his first trip as president. The U.S. economy was in tatters then — and few, if any, places were worse off than Elkhart.”

On the trail

Donald Trump holds a rally in Sacramento, CA at 10:00 pm ET… Hillary Clinton stumps in Newark, NJ, while her husband Bill Clinton hits Cranford, NJ… And Bernie Sanders spends his day in California. Don’t forget to check out the political unit’s rolling minute-to-minute coverage of all the latest 2016 developments at theOn the Trail liveblog at NBCNews.com.