"When Mexico sends its people, they’re not sending their best. They’re not sending you," he said. "They’re sending people that have lots of problems, and they’re bringing those problems with us. They’re bringing drugs. They’re bringing crime. They’re rapists."
Since then, Trump, now the presumptive Republican nominee, has boasted that he's won among women, among men, among poor and among the rich. But there is one crucial group he's not winning with -- minority voters.
In the latest ABC News/Washington Post poll on April 14, Trump was more unpopular than popular by 20 points among whites. That number balloons to 65 points in unpopularity among nonwhites, including 84 and 66 among blacks and Hispanics, respectively.
And as the standard-bearer of his party, that means the Grand Old Party now appears to have its own grand ole problem; how to salvage the damage wrought by their new nominee.
"He's a polarizing candidate,” said one former RNC staffer who left her position in the fall of last year, after Trump had already become a phenomenon.
The former staffer, who requested anonymity to be able to speak candidly, says that Trump’s rhetoric and actions are incongruous. The Trump campaign declined comment for this article.
“He says he wants to win more minority voters. You can't do that and at the same time incite violence...and not condemning racism where it exists,” she said. “Those are the types of things that just common sense things.”
The RNC's Efforts
The RNC, in the aftermath of the 2012 election, sought to correct the situation. It hired additional staffers who stayed on to help with down-ticket races. The RNC implemented the Republican Leadership Initiative, an outreach mechanism to get voters of color registered as GOP organizers. Jenny Korn, the Deputy Political Director for Strategic Initiatives at the RNC, says that more than 3,000 fellows have been registered.
She gets excited when talking about voter registration and staffing. "We are ensuring that the campaign encompasses and engages those communities; we will have the most diverse staff that the RNC has ever had," she told ABC News in late April.
One of the new hires is Telly Lovelace, the new National Director of African-American Initiatives. He notes the Radio One Initiative that the RNC has rolled out, to partner with hundreds of urban radio stations across the country.
He says that the RNC has steadily been building its relationships with voters of color and has seen results.
But the RNC refused to discuss Trump's impact on its efforts.
Trump and a Lack of Outreach
"Jeb gave a landmark speech to the Urban League last summer in which he laid out his philosophy to go everywhere, "campaign everywhere," and "ask for every vote." Republicans of the Jack Kemp-Jeb Bush model were what the party needed to dig itself out of its hole with minority voters," Badger said.
Trump's campaign, however, is noticeably devoid of any such outreach or any formal staffer or group assigned to cull votes from minority populations. The vast majority of his events are large campaign rallies; the audiences have been largely white.
There are some who have rallied around Trump. The National Diversity Coalition for Trump is a group aimed at reaching voters of color but it is not officially affiliated with the campaign, and campaign officials stressed that it is an independent organization. It consists of several sub-groups, including "Arab-American [sic] for Trump" and "Mexican-American for Trump."
Bruce LeVell, a jeweler from Atlanta, Georgia, is one of the group's founders and its executive director. Other members include Omarosa Manigault, best known from "The Apprentice", and Michael Cohen, counsel for the Trump organization.
LeVell says that he's had many African-American and Hispanic-Americans reaching out to join in.
"Everyone on there is pretty much a referral- referred by someone in some level of leadership in their community. It's not so much that they're staunch Republicans but they believe in the candidate," he said.
Sajid Tarar, a former lawyer, heads up the "Muslim Americans for Trump" subgroup. He says that he's part of the "angry Americans" who are sick with Washington and says that he has done outreach events in Baltimore (where he lives) that have seen 200 people come out. He also does outreach in mosques.
"Some of them they are very tough, [they have] very harsh words. They tell us we are traitors because the man is against Islam and you are promoting them," Tarar said. He adds, "There are some that are listening to us and are paying attention."
He bristles against the accusation that Trump's proposed Muslim ban makes him Islamophobic or xenophobic and says that he's knows Trump will clarify once he gets in office.
"But no he's going to explain, he's going go into the details...when he goes into the White House," Tarar said.
So What Now?
But there will be lots of explaining to do, lots of ground for the Party to make up, if polls are correct.
"The party began last year at huge deficit with black and brown voters. Rather than make progress, Trump has dug the GOP in a hole much, much deeper than previously imaginable," Badger mused. He does see a possibility for Trump to do well with Black male voters "with his "Mexicans are stealing your jobs" demagoguery."
So much of the RNC's outreach was community-based. Staffers go door-to-door in Latino communities, a black church in Cleveland gets a visit from RNC Chair Reince Priebus, and staffers welcome Asian and Pacific Islander Americans during naturalization ceremonies. Now, they not only have to win these voters over to the party, but defend their nominee from accusations of prejudice and divisive rhetoric; which Democrats have already begun to use to their advantage.
When Trump decided to celebrate Cinco de Mayo by tweeting a picture of himself eating a taco bowl (an American dish), Hillary Clinton was swift to respond.
“I don't think he's a racist, I don't think anyone thinks Trump is a racist; he is detached from how to do with some of these constituency groups and he has to learn quickly,” said the former RNC staffer who requested anonymity.
She says that he’s proven adept at learning, but fears the his early comments will continue to haunt him. “I do think he has done damage early on, the same way he has done with women," she said.
The former RNC staffer says that Trump can’t afford to not change his strategies and notes that he needs to build diversity within his own staff.
“It’s absolutely worth it," she said. "It’s not just about winning, it's the right thing to do."