Donald Trump insisted Monday that the Republican establishment is against him, but conceded that party leaders are warming to his candidacy as a better alternative to rival Sen. Ted Cruz’s presidential bid. In the first portion of a wide-ranging interview with CNN’s Wolf Blitzer just a week before Iowans head to the caucuses, Trump touted his strong lead in the polls, once again raised the “problems” Cruz faces due to his Canadian birthplace and undisclosed campaign loans and explained why he joked about shooting somebody in the middle of New York’s 5th Avenue. Trump also explained why establishment leaders are more prepared to back his presidential bid over that of Cruz, the Texas senator who has cast himself as a principled lawmaker but whom critics call inflexible. Trump, for his part, called Cruz a “nasty person.” “I think the establishment actually is against me, but really coming on line because they see me as opposed to Cruz who is a nasty guy who can’t get along with anybody,” Trump said. “At a certain point you’ve got to make deals.” And Trump pointed to Cruz’s 21-hour protest on the Senate floor in fall 2013 – in an unsuccessful bid to defund the Affordable Care Act – as proof that “Ted cannot get along with anybody.” “We can’t have a guy who stands in the middle of the Senate floor and every other senator thinks he’s a whack job,” Trump said. “You have to make deals. You have to get along. That’s the purpose of what our founders created.” While Trump’s candidacy has from the start faced a barrage of criticism from the political and consultant classes in Washington, several establishment Republicans have said lately that they would sooner back Trump than Cruz. That has in turn become a new attack line by Cruz as he battles Trump for a first-place finish in the Iowa caucuses, which polling a week out shows could go either way. Cruz has taken to slamming Trump as the establishment’s new hope, suggesting that those in the Washington power club are abandoning Florida Sen. Marco Rubio in favor of the mogul. Trump also dismissed criticisms he took after saying at a rally Saturday that he could shoot somebody in the middle of a crowded street and not lose any supporters. “I could stand in the middle of 5th Avenue and shoot somebody and I wouldn’t lose voters,” Trump said Saturday at an event in Sioux Center, Iowa. Trump told Blitzer that he “was joking” and noted that his audience of supporters laughed along with him as he made those remarks. “Of course I’m joking,” Trump said. “And the purpose of that is to say the people love me. You know, they want to stay with me. They’re loyal. They’re tired of seeing our country being pushed around and led by people that are stupid people. They’re tired of that.” And once again Trump was unable to resist lobbing attacks at former Florida Gov. Jeb Bush, the establishment darling whom Trump has repeatedly cast as “low-energy” – a foil to Trump’s brash, unforgiving attitude. Trump said Monday that Bush has “disgraced himself” by failing to gain momentum for his presidential bid despite Bush’s campaign and outside allies spending tens of millions of dollars to buoy his campaign. “What Jeb Bush has done to the Bush family is very sad. Then he brings out his mother. I said, ‘Jeb, your mother can’t help you with ISIS, she can’t help you with China, she can’t help you with these people, Jeb. You got to do it yourself,’” Trump said, remarking on Bush’s mother appearing in an ad in support of her son’s bid. “But here’s a guy who spends over a hundred million dollars and he’s nowhere. I mean he’s, he’s – I think he’s disgraced himself, to be honest with you,” the businessman said.