'This Week' Transcript: Gov. John Kasich, Sen. Bernie Sanders, and Reince Priebus

— -- THIS IS A RUSH TRANSCRIPT FOR 'THIS WEEK' ON April 3, 2016 and it will be updated.

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UNIDENTIFIED MALE: Starting right now on THIS WEEK WITH GEORGE STEPHANOPOULOS, Trump's terrible week -- the billionaire frontrunner down big in Wisconsin, after seeing his top adviser arrested, sparking a firestorm over abortion and getting slammed on his foreign policy.

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DONALD TRUMP (R), PRESIDENTIAL CANDIDATE: I'm not sure which is worse, dealing with the party people or dealing with the press.

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UNIDENTIFIED MALE: Now, is Trump more vulnerable than ever? and could a Wisconsin loss make a convention clash inevitable?

The Republican Party chair and Trump rival John Kasich are both here.

Plus, fed up and feuding...

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HILLARY CLINTON (D), PRESIDENTIAL CANDIDATE: And I'm also a Democrat. That's kind of important.

SEN. BERNIE SANDERS (I-VT), DEMOCRATIC PRESIDENTIAL CANDIDATE: Secretary Clinton owes us an apology.

UNIDENTIFIED MALE: As Bernie Sanders gains in the polls, the Democratic fight for the nomination gets heated.

Bernie Sanders joins us live.

From ABC News, it's THIS WEEK.

Here now, chief anchor George Stephanopoulos.

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GEORGE STEPHANOPOULOS, ABC HOST: Was this week the tipping point for Donald Trump?

Imagine any other candidate enduring the week he had. Imagine one dealing with it the way he did.

It began with a battery charge for campaign manager, Corey Lewandowski, after surveillance video proved he grabbed reporter Michelle Fields at a Trump rally last month.

Now, most candidates would discuss the staffer. Not Trump, he blamed the reporter.

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TRUMP: She didn't almost fall to the ground. She -- he -- he got in her way. And by the way, she was grabbing me.

Am I supposed to press charges against her?

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STEPHANOPOULOS: Then there was Trump's trouble with abortion.

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CHRIS MATTHEWS, MSNBC HOST, "HARDBALL": Do you believe in punishment for abortion, yes or no, as a principle?

TRUMP: And the answer is that there has to be some form of punishment.

MATTHEWS: For the woman?

TRUMP: Yes, there has to be some form.

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STEPHANOPOULOS: After the predictable firestorm...

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SEN. TED CRUZ (R-TX), PRESIDENTIAL CANDIDATE: Being pro-life is not only about defending the unborn children, it's also about defending the mothers.

CLINTON: Donald Trump is showing us exactly who he is and we should believe him.

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STEPHANOPOULOS: Trump forced to backtrack.

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TRUMP: The laws are set now on abortion and that's the way they're going to remain.

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STEPHANOPOULOS: Another clarification followed. Only the late night comics seemed to be happy with how it ended up.

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UNIDENTIFIED MALE: So at this point, Donald Trump has to be pro-choice because he's made all of the choices.

(LAUGHTER)

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STEPHANOPOULOS: And on foreign policy, Trump shattered more than half a century of security policy by hinting at how he would use nuclear weapons and suggesting Japan and South Korea should considering building nuclear arsenals of their own.

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GOV. JOHN KASICH (R-OH), PRESIDENTIAL CANDIDATE: You wonder about his hand or his thumb getting any close to the critical button that presidents are in charge of.

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STEPHANOPOULOS: President Obama weighed in, too.

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