WASHINGTON (AP) — The Latest on campaign 2016 (all times Eastern):
Six people are being evaluated by emergency medical crews after an envelope containing a white powdery substance was mailed to a Donald Trump campaign office in New York City.
Emergency crews were called to Trump Tower in Manhattan around 8 p.m. Thursday.
Police say a Trump staffer opened the letter containing the powder and immediately called police. It was unclear if the envelope also contained a letter.
The six people who were isolated and evaluated at the scene included five Trump staffers and a police officer who responded to the call.
In March, an envelope containing a non-hazardous white power and a threatening letter was sent to the Manhattan apartment of Donald Trump's son, Eric.
Thousands of supporters have turned out for Donald Trump as the Republican presidential brought his campaign to Southern California, predictably sparking shouting matches with counter-demonstrators.
Heated words were exchanged after people wearing expletive-laden anti-Trump shirts began to taunt people waiting in line to attend Trump's speech in an amphitheater at the Orange County Fairgrounds in Costa Mesa.
Trump supporters surrounded the demonstrators and shouted: "Build that wall! Build that wall!" — a reference to Trump's call to create a barrier between the United States and Mexico to stop illegal border crossers.
Later, county sheriff's deputies in riot gear and on horseback formed a barrier between a small group of anti-Trump demonstrators and the pro-Trump crowd.
Police say there have been no arrests.
The GOP presidential contenders are facing an early test at the Republican Party convention in California, a state whose June primary could hold the decisive delegates in the fight for the presidential nomination.
Donald Trump, who made his mark as a political outsider, is scheduled to speak Friday to hundreds of GOP insiders — the activists and elected officials who make up the core of the state party.
The reception he receives will be noteworthy: the billionaire businessman rarely speaks to Republican establishment groups, and he's railed against what he calls a rigged party system for the nomination.
In addition to Trump, Ohio Gov. John Kasich speaks on Friday night. Texas Sen. Ted Cruz and his choice for running mate, former presidential candidate Carly Fiorina, speak on Saturday.
New Jersey Gov. Chris Christie says his wife was not rolling her eyes at Republican presidential front runner Donald Trump when he said Hillary Clinton would not win so many votes if she were a man.
Christie on Thursday called the description of Mary Pat Christie by the media "silliness."
He says that as the recipient of more eye rolls from his wife than "any human being on earth" he could confirm it was not an eye roll.
Trump said Tuesday night that Clinton wouldn't get 5 percent of the vote if she were a man.
Mary Pat Christie could be seen looking one direction then another. Voters circulated video on social media and many called it an eye roll.
Donald Trump has won 57 delegates in Pennsylvania, picking up endorsements from seven more on Thursday.
Trump won the Pennsylvania primary, which guaranteed him 17 delegates. An additional 54 delegates were elected directly by voters — three in each congressional district. These delegates are free to support the candidate of their choice.
The Associated Press has confirmed that 40 of them support Trump. Four said they support Cruz and nine are uncommitted. One delegate race was too close to call.
These delegates, however, change their minds.
Trump has 80 percent of the delegates needed to win the Republican nomination. He needs 48 percent of the remaining delegates to clinch the nomination and avoid a contested convention.
The AP delegate count:
Needed to win: 1,237.
Jeb Bush says Republican presidential candidate Ted Cruz made a "smart move" in choosing Carly Fiorina as his running mate.
Bush, a former contender for the GOP nomination, said Thursday that front-runner Donald Trump is "not a serious person," especially on foreign policy matters.
The CNN interview was the first public appearance by Bush since dropping out of the race in February.
Bush, who has endorsed Cruz, praised Fiorina as "talented" and "tough." He says she "takes on Trump really well ... and she takes on Hillary Clinton very well. I thought it was a smart move."
As for Trump, the country needs "a president with a steady hand." Bush told CNN.
He added: "The successful presidents have been clear about their vision, have laid out the agenda, and with foreign policy, our friends know we have their back and our enemies fear us ... He's proposing the exact opposite."
Bobby Knight, a Donald Trump backer, is praising former President Harry Truman for "having the guts" to drop the atomic bomb on Japan — and said Trump would "do the same thing."
Knight, the famed Indiana University basketball coach, introduced Trump at an Evansville rally on Thursday and was then summoned back to the stage by the celebrity businessman.
Knight mocked the idea of Trump needing to "act presidential" and said similar criticism had been levied against Truman, whom he felt was "one of the three great presidents of the United States."
Knight said Truman "saved millions of American lives" by "having the guts to drop the bomb in 1944," though the weapon was actually utilized the following year.
He then pointed to Trump and said "here's a man who would do the same thing, because he's going to become one of the four great presidents of the United States."
Donald Trump's top advocate in the Senate is refusing to defend the GOP front-runner's remark that Hillary Clinton is playing "the woman card."
Alabama Sen. Jeff Sessions said Thursday that he's "not goin' to be the person that has an answer for everything a candidate says in the race."
Asked to defend Trump's assertion about the former secretary of state, senator and lawyer, Sessions said, "I think there can be no discrimination against women and I do not believe that Donald Trump would ever discriminate against a woman."
He would not say whether he agrees with Trump about Clinton, the Democrats' lead candiate for president. Republicans have long struggled to attract women to the party.
Trump stood by his remark when asked about it Thursday on NBC's "Today" show, adding that "no one respects women more than I do."
The world is fascinated by Donald Trump. It's just as blindsided as many Americans about his rise and nearly at a loss to understand what he would do as president.
Foreign-policy elites around the globe speak of Trump as a loose cannon, a "roller-coaster," ''unpredictable," ''dangerous" and, perhaps above all, a "mystery."
But they can't avert their gaze from a Republican presidential race that turns on the billionaire's every word.
The handwringing is not universal.
Some analysts saw hints in Trump's foreign policy speech this week that he would take a reasoned approach in office, his out-there instincts curbed by the realities of government, and some thought relations with China and Arabs might improve.
And Trump is no outlier in contending the United States is too entangled abroad.
Donald Trump is saying that the Republican nomination race "is over" if he wins in Indiana next week — but is still railing against what he calls the "crooked way" the party picks its nominee.
Trump, speaking in Evansville on Thursday, claimed his rival Ted Cruz was unfairly winning delegates.
The Republican front-runner said Cruz "can only successfully win support by wooing delegates with "steaks" and "trips."
Trump then said the winner "should be based on votes, not on whether people like a certain steak from a certain place."
Donald Trump has added endorsements from five more delegates in Pennsylvania, giving him 147 delegates from Tuesday's primaries.
Ted Cruz and John Kasich won a total of eight.
Trump now has 80 percent of the delegates needed to win the Republican nomination for president. Going forward, Trump needs just 47 percent of the remaining delegates to clinch the nomination and avoid a contested convention.
The AP delegate count:
Needed to win.
Donald Trump is once again trotting out famed former Indiana University Bobby Knight as he campaigns across the Hoosier State.
Knight, who endorsed Trump in Indianapolis on Wednesday night, appeared with the Republican front-runner again Thursday afternoon in Evansville.
Trump praised Knight's coaching record — which included three national titles and an undefeated season — and then the coach came out to echo his praise of the celebrity businessman.
Knight said Trump was "not a Democrat or a Republican at heart" but just "a great American" and had the "ideal background" to become president.
Knight also said that, as coach, he was selective in choosing his players and, gesturing toward Trump, said "That son of a b---h" could play for me.
Trump, who has a commanding delegate lead over rival Ted Cruz, has said that the nominating race "would be over" if he wins the Indiana primary next week.
Ted Cruz says John Boehner (BAY'-nur) let his "inner Trump come out" when the former House speaker described Cruz as "Lucifer in the flesh."
Cruz is campaigning ahead of Indiana's Republican presidential primary on Tuesday and he took issue with Boehner's barb.
Boehner told a Stanford University audience this week that he has "never worked with a more miserable son of a bitch in my life" than Cruz — who's a Texas senator.
The comments were reported by Stanford's student newspaper.
Cruz says he never actually worked with Boehner. And the White House candidate says he'd be surprised if the two politicians ever exchanged more than 50 words.
Cruz has this message for voters: "When John Boehner calls me Lucifer, he's not directing that at me. He's directing that at you."
Former House Speaker John Boehner is unloading on Texas Sen. Ted Cruz, calling him "Lucifer in the flesh."
"I get along with almost everyone, but I have never worked with a more miserable son of a bitch in my life," Boehner tells students at Stanford University according to The Stanford Daily.
The Ohio Republican resigned last fall under pressure from conservatives allied with Cruz. Boehner's well-known contempt for the Texan stems in part from Cruz's role forcing a partial government shutdown in 2013. Boehner said he and Donald Trump are "texting buddies" and he would vote for Trump, but not Cruz.
Of Ohio Gov. John Kasich Boehner said he "requires more effort on my behalf than all my other friends . but he's still my friend, and I love him."
Carly Fiorina is explaining the rules of the Republican Party to rival Donald Trump as she looks to assert why the race for the Republican nomination could go to a contested convention.
In an interview on MSNBC's "Morning Joe" Thursday, a day after Ted Cruz named her as his running mate, Fiorina said Trump will get "shellacked by Hillary Clinton" if he is the nominee for the Republican Party, but asserted that he could lose the nomination if he doesn't get the majority.
"Donald Trump just figured it out, but wow, this system has been in place for a very long time," she said, referring to his claims that he should be named the nominee even if he falls slightly short of the required 1,237 delegates needed to win the nomination.
"I think what we need in November is a very clear choice," she said.
Bernie Sanders' wife and adviser Jane Sanders says his campaign will do well in the remaining contests because they are open primaries, which she describes as "more democratic."
In an interview with MSNBC's "Morning Joe" Thursday, Jane Sanders noted that Bernie Sanders won Rhode Island on Tuesday, which was an open primary, allowing independents as well as Democrats to vote for her husband.
"If you close the primary and you only have people who have been in the Democratic Party for years, what you are doing is effectively shutting the door on the millions of people that Bernie has brought in to the political process during this election," she said.
She also said that his campaign intends to continue through the final contest in California, despite a revelation Wednesday that the campaign plans to lay off hundreds of field staffers and other aides.
An astonishing Republican presidential primary season has taken another unusual turn.
Texas Sen. Ted Cruz has picked Carly Fiorina as his running mate — even though he's mathematically unable to become the GOP nominee through the regular voting process.
It's the move of a candidate desperate to block front-runner Donald Trump, who is growing only stronger as the primary contest presses deeper into the spring.
Trump now has 80 percent of the delegates he needs for the Republican nomination, though he could still fall short and have to battle Cruz at a contested convention. Trump must win 48 percent of the remaining delegates to avoid that scenario.
Cruz's White House hopes now rest largely on Tuesday's primary in Indiana. That's where he announced Wednesday that he is tapping Fiorina as his vice presidential pick.