NEW YORK -- Donald Trump is struggling in his efforts to unify the Republican Party behind his presidential campaign, the difficulty immediately underscored Thursday by a startling exchange of negative comments with GOP House Speaker Paul Ryan who said he was not ready to support him.
Although Trump is now the party's presumptive nominee, Ryan said Thursday, "I'm just not ready to do that at this point. I'm not there right now." Still, he added, "I hope to. And I want to," in comments on CNN's "The Lead."
Trump responded, in a statement released by his campaign, that he was "not ready to support" Ryan's agenda as the party's leader in the U.S. House. "Perhaps in the future we can work together and come to an agreement about what is best for the American people," he said.
Two days after the Indiana primary all but sealed Trump's victory as the man who will lead their election ticket in November, he is appealing to big-money donors he blasted during the primaries as he takes his first steps toward raising the massive amounts of cash he'll need for the general election campaign.
That effort was hardly helped by the rejection -- for now -- by Ryan, the Wisconsin congressman who was Mitt Romney's running mate in 2012. In addition, Romney and former President George W. Bush said they do not plan to attend the party's national convention in July.
Trump is aiming to broaden his primary insurgency into a full-fledged general election campaign, reaching out to party heavyweights and trying to repair his sometimes-strained relationships with the Republican National Committee.
Upbeat still, Trump said in a brief interview with The Associated Press that his message has made the GOP "the hottest party around."
His campaign is trying to convert that energy into dollars.
On Thursday, Trump named a finance chairman, Steven Mnuchin, a private investor with ties to New York and Hollywood. Mnuchin "brings unprecedented experience and expertise" to the fundraising operation, the campaign said.
And Trump is taking pains to reassure party leaders that he wants to help Republican Senate and House candidates, some of whom are openly worried that Trump at the top of the GOP ticket will be a drag on their own campaigns.
Earlier this week, Trump's final GOP foes, Ted Cruz and John Kasich, dropped out, clearing his path. Still, many party leaders, including Ryan, Bush and Romney, are keeping Trump at arm's length.
Their reluctance to embrace him sends an unmistakable signal to their fundraising networks, which include most of the GOP's best-connected donors.
"You might have a lot of these donors sit on the sidelines," said Spencer Zwick, who led Romney's fundraising efforts and now serves as Ryan's national finance chairman.
Trump, a billionaire who paid for most of his primary campaign by himself, acknowledges he would have to sell some of his holdings to muster the hundreds of millions of dollars for a general election bid, something he says he doesn't necessarily want to do.
He said Thursday he would be "putting up substantial money toward the general election," following the $36 million in loans he previously made.
Yet he's also beginning to take a more traditional route for his likely battle with Hillary Clinton, a Democratic fundraising powerhouse.
Mnuchin, who has never led a major political fundraising team, faces a gargantuan task.
Many major GOP donors have never heard of him -- or even know how to pronounce his name (muh-NOO-chihn). Like his new boss Trump, Mnuchin has a record of giving both to Republicans and Democrats -- including Clinton during her 2008 presidential run.
Anthony Scaramucci, a New York investor and Republican donor, said that Mnuchin, a friend with homes in New York and California, has Wall Street and Hollywood ties and "is a great team-builder." Scaramucci, who earlier raised money for failed GOP candidates Scott Walker and Jeb Bush, said he plans to be part of that team.
Trump also hopes to tap into the RNC's existing fundraising network, but faces hurdles.
"High-dollar donors need to be convinced that Trump is going to be a serious candidate and won't embarrass them," said Charlie Spies, a veteran Republican operative with deep ties to party fundraisers.
This is all new to Trump. Through the end of March, he had raised $12 million, mostly from fans who clicked the "donate" button on his website or bought wares such as the ubiquitous red ballcap emblazoned with his slogan, "Make America Great Again," campaign finance documents show.
That contrasts with Clinton, who has raised some $187 million so far and began her general election fundraising effort back in November that can solicit huge checks for her campaign, the Democratic National Committee and state parties.
Trump's lean campaign team will likely depend heavily on the Republican National Committee as he shifts to the 50-state task ahead. The RNC is counting on him to reciprocate by helping fund its nationwide data operation and staffing expansion.
Trump will also name a transition team and a vice-presidential search committee. He told the AP that he will announce his running mate choice at the July convention.
Bykowicz reported from Washington. Terry Spencer in West Palm Beach, Florida, and Steve Peoples in Washington contributed reporting.
