With the general election in his sights, Republican Donald Trump delivered a sober foreign policy address Wednesday aimed at easing fears about his temperament and readiness to be commander in chief. Rival Ted Cruz made a desperate attempt to jolt the GOP race by tapping Carly Fiorina as his running mate.

Both moves underscored Trump’s commanding position in the GOP race. Though the businessman must keep winning primaries in order to clinch the nomination before this summer’s national convention — he needs 48 percent of delegates still up for grabs — he has breathing room to start making overtures to general election voters. All Cruz can do is throw obstacles in his path.

Cruz announced Fiorina as his vice presidential pick during a rally in Indiana, a state he must win next week in order to keep his White House hopes alive. He cast the unusual announcement as a way to give voters confidence in their choice if they vote for him.

"You deserve to know exactly where a candidate stands," he said.

Fiorina immediately went after Trump and Democratic front-runner Hillary Clinton, embracing the aggressive role of a No. 2 on the White House ticket. She cast Trump and Clinton as a pair of liberals who would do little to shake up Washington.

"They’re not going to challenge the system — they are the system," Fiorina said.

Trump mocked Cruz at a rally in Indianapolis Wednesday night, saying, "Cruz can’t win, what’s he doing picking vice presidents?"

"He is the first presidential candidate in the history of this country who’s mathematically eliminated from becoming president who chose a vice presidential candidate," Trump said.

Cruz and Ohio Gov. John Kasich are trying to keep Trump from securing the 1,237 delegates he needs to clinch, thereby pushing the Republican race toward a contested convention. But Trump strengthened his standing this week with a sweep of five Northeast primaries, giving him 80 percent of the delegates he needs.

Trump headed to Indiana Wednesday as well, following his address in Washington.

Before an audience of foreign policy experts in Washington, Trump outlined a doctrine that he said would put American interests first, leaving allies to fend for themselves if they don’t contribute financially to back up security agreements. He vowed to send U.S. troops into combat only as a last resort, a break from years of hawkish Republican foreign policy.

"Our goal is peace and prosperity, not war and destruction," he declared in the 38-minute address that was heavy on broad statements and light on specific policy details. Unlike his rambunctious, freewheeling rallies, Trump read prepared remarks in a measured tone off a teleprompter.

He also used the address to target Clinton, his expected opponent in a general election. He assailed her handling of the deadly 2012 attack on Americans in Benghazi, Libya, and said that during her tenure as secretary of state, the U.S. had a "reckless, rudderless and aimless foreign policy."

Clinton’s campaign sees foreign policy as an area ripe for a sharp general election contrast with Trump, given her years at the State Department and his lack of experience. In a campaign conference call Wednesday, Clinton supporter and former Secretary of State Madeline Albright called Trump’s views "incoherent."

"I’ve never seen such a combo of simplistic slogans and contradictions and misstatements in one speech," Albright said.

Like Trump, Clinton emerged from this week’s Northeastern primaries with a stronger claim on her party’s nomination. With four victories Tuesday, she now has 91 percent of the delegates needed to clinch the Democratic nomination.

Vermont Sen. Bernie Sanders, campaigning in Indiana as well Wednesday, conceded that the delegate math was not in his favor. He said his campaign still aims to win the nomination but will also seek to assemble as many delegates as possible to influence the party’s platform and message.

"Our job, whether we win or whether we do not win, is to transform not only our country but the Democratic Party, to open the doors of the Democratic Party to working people and young people and senior citizens in a way that does not exist today," Sanders said.

Cruz hoped that adding Fiorina to his potential ticket would be a draw for Republicans desperate to keep Clinton out of the White House. Fiorina, the former Hewlett-Packard chief executive, was frequently praised for her tough criticism of Clinton during her own presidential campaign and irritated Trump with her sharp retorts during GOP debates.

Since dropping out, she has become Cruz’s most active surrogate, making frequent campaign appearances alongside him and on her own.

Candidates typically wait until they’ve secured their party’s nomination before picking a running mate, in part to avoid appearing to be getting ahead of the will of the voters.

But in Cruz’s case, the announcement seemed aimed at keeping up the idea that he has a claim to the nomination and potentially attracting more voters in Indiana and other remaining states — including Fiorina’s home state of California.

Asked on "Fox & Friends" about Cruz naming a running mate, Trump said, "To me it looks ridiculous, he’s not going to get the nomination."

Trump emerged with more than 50 percent of the Republican votes in Pennsylvania, Connecticut and Maryland, and scored over 60 percent in Delaware and Rhode Island. Similarly, Clinton won convincingly in four of the five contests, scoring 56 percent in Pennsylvania and 63 percent in Maryland — the two biggest contests of the night. Sanders won the Rhode Island primary with 55 percent of the vote.

(Copyright (c) 2016 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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