Trump shows new vulnerabilities -- and has only himself to blame

“Either these are the weeks we discovered he had weaknesses he couldn’t overcome, or these are the weeks when he and his team realized they had to get better,” said former House speaker Newt Gingrich (R-Ga.). “If he makes the transition to being a really professional presidential candidate, he will be really formidable. And if he does not, he will not be the nominee.”

Trump campaign manager Corey Lewandowski insisted that there will be no major shift in strategy…

In Wisconsin, Our Principles PAC, an anti-Trump group, spent $2 million and had a robust, across-the-board operation: television and digital ads, billboards, direct mail, phone calls, and absentee and get-out-the-vote programs.

“Trump didn’t take the time to build out an organization that could go all the way, and he doesn’t have the infrastructure in various states, to the point he’s not fielding full delegate slates,” said Brian Baker, a senior strategist for the group.