WASHINGTON — Republican Donald Trump signaled a shift toward "more meat on the bone" in his policy speeches Wednesday amid new signs of campaign discord, a day after his stinging Wisconsin defeat emboldened his critics and pushed the GOP closer to its first contested national convention in four decades.

Democrat Hillary Clinton, meanwhile, embraced a tougher approach with liberal rival Bernie Sanders, who beat her in Wisconsin. Still, Sanders' string of recent primary victories has done little to erode the former secretary of state's overwhelming delegate lead as the 2016 primary season lurches toward a high-stakes contest in two weeks in New York.

"The core issue in his whole campaign doesn't seem to be rooted in an understanding of either the law or the practical ways you get something done," an aggressive Clinton declared in an interview on MSNBC. She suggested Sanders "hadn't done his homework" on specific prescriptions needed to address economic inequality.

As the Democratic front-runner tried to undercut Sanders' recent momentum, Trump's grasp on his party's presidential nomination appeared far more tenuous. Senior Trump adviser Barry Bennett shrugged off the Wisconsin loss to Texas Sen. Ted Cruz, but he also said the billionaire businessman would soon begin to deliver a series of "presidential, substantive" speeches on his policy priorities. That list likely includes immigration, trade, defense and taxes.


"That's coming," Bennett said of the shift. "There will be more and more meat on the bone as we go forward."

At the same time, Trump's team quietly worked to resolve problems with its young delegate outreach operation, a critical tool as the primary campaign speeds toward the possibility of a contest convention. The tension centers on campaign manager Corey Lewandowski, whose management style has alienated some would-be allies on the ground in key states.

For example, the campaign over the weekend fired the person running its Colorado operation ahead of the state's convention on Saturday. The move was confirmed by a person with direct knowledge of the staffing situation who spoke on the condition of anonymity to discuss internal deliberations.

The issues come as leading Democrats and Republicans acknowledge a growing likelihood that Cruz could wrestle the presidential nomination away at the GOP national convention in July.

While Trump maintains a big delegate lead, Cruz took a big step forward with his win in Wisconsin. The senator has no realistic path to claim the nomination by the end of the primaries on June 7, but he might force a contested convention by blocking Trump from getting a majority of delegates in the state-by-state voting.

Trump must win 57 percent of the remaining delegates to clinch the nomination before the convention. So far, he's winning 46 percent.

Wisconsin Gov. Scott Walker, who hopes the year will play out in Cruz's favor, said the Republican race was "very likely" headed to an open convention.

"Ted Cruz will win on the second ballot if not on the way in, and he will unite the party," Walker said on WTMJ radio in Milwaukee.

New Hampshire Sen. Kelly Ayotte, asked if she's coming around to the idea of Cruz as the nominee, said, "I'm coming around to more like, 'It looks like it will be a very interesting convention.'"

At the same time, Clinton allies were broadening their attacks against Trump to include Cruz, a first-term senator who has often alienated Democrats and Republican alike in Washington.

"One of the scariest parts of Donald Trump's insulting, demeaning and dangerous attack on women is that Ted Cruz might actually be even worse for women," said Anne Caprara, who leads the pro-Clinton group, Priorities USA. That group worked with the campaign arm of Planned Parenthood to unveil an anti-Trump internet ad on Wednesday.

Meanwhile, attention in both parties shifted toward New York's April 19 primary elections, where Clinton and Trump hold big leads in early polls. Trump was to address voters Wednesday night in a homecoming of sorts for the New York City native.

Former gubernatorial candidate Carl Paladino, one of Trump's state co-chairs, said the campaign received 18,000 requests for Wednesday's event, although the venue holds just 3,000 people.

Said Paladino, a Buffalo-based businessman: "We've seen people just coming up saying, 'Where has he been?' Thank God he's here."

As for possible friction in the campaign, Paladino said he's had no problems with Trump's campaign manager.

"They do have a small staff — probably smaller than they should have — but these guys work 24/7," he said. "I don't know how they keep their senses about them."

Cruz, campaigning Wednesday in New York as well, lashed out at "New York values," which he called "the values of the liberal, Democratic politicians."

Peoples reported from Washington. Associated Press writers Jill Colvin in Jersey City, New Jersey, Hope Yen, Stephen Ohlemacher, Andrew Taylor, Erica Werner in Washington, Jonathan Lemire and Michael Balsamo in New York, and Scott Bauer in Madison, Wisconsin, contributed.