Mitt Romney told members of the nation’s oldest civil rights organization on Wednesday that he would be a better president for the nation’s black families than President Obama has been. It was a bold appeal aimed at some of Obama’s most ardent supporters and cast Romney as someone willing to forcefully speak his piece even in unfriendly territory.

But the presumptive Republican nominee’s speech here received the most hostile reaction from any campaign audience this year, and Romney appeared unsettled by three rounds of loud boos.

“If you want a president who will make things better in the African American community, you are looking at him,” Romney said. When the crowd booed and hissed, he said, “You take a look.”

Romney made a direct appeal for support from black voters, who polls show overwhelmingly back the reelection of the nation’s first black president. Romney said his policies would help black families succeed in a sputtering economy, with rising federal debt and poor schools.

He also highlighted his father’s civil rights legacy as governor of Michigan and tried to build a bridge with black voters by talking about their shared faith in God and support of strong families.

“I believe that if you understood who I truly am in my heart, and if it were possible to fully communicate what I believe is in the real, enduring best interest of African American families, you would vote for me for president,” Romney said. “I want you to know that if I did not believe that my policies and my leadership would help families of color — and families of any color — more than the policies and leadership of President Obama, I wouldn’t be running for president.”

Romney said that black families have suffered disproportionately under the Obama presidency, noting that the unemployment rate for African Americans rose to 14.4 percent last month, while the overall rate was 8.2 percent.

“If equal opportunity in America were an accomplished fact, then a chronically bad economy would be equally bad for everyone,” he said. “Instead, it’s worse for African Americans in almost every way.”

Romney asked black voters to give him “a fair hearing” and promised that if he is elected, and if the NAACP invites him to return, he would address the group next year and “count it as a privilege.”

“In campaigns at their best, voters can expect a clear choice, and candidates can expect a fair hearing — only more so from a venerable organization like this one,” he said.

The hundreds of African Americans in attendance at the NAACP’s national convention in Houston gave Romney polite although subdued applause. But he received a loud and sustained spattering of boos when he referenced his opposition to the health-care law he called “Obamacare,” when he said Obama’s policies are not helping to create jobs and when he said he would be a better president for black families. Many portions of his speech received reserved cheers, such as his promise to defend traditional marriage, and many black voters in the audience stood to applaud him when he finished.

Although Romney appeared surprised by the booing, a campaign aide said he took it in stride, and his advisers said they were not bothered by the reaction. Indeed, they considered the speech gutsy. One adviser said privately that Romney has presented the same agenda to every audience since the start of the campaign and did not back down from advocating policies here that he knew black voters generally oppose, such as repealing Obama’s health-care overhaul.

“We understand that folks aren’t going to agree with us 100 percent, but at the end of the day, I think Governor Romney’s message was bold, he’s said things that needed to be said, he’s said things he’s always said about ending Obamacare and about bringing this economy back,” Tara Wall, the campaign’s black-outreach adviser, told reporters.

Later Wednesday, at a fundraiser in Montana, Romney said he gave the same speech to the NAACP that he gives to supporters.

“I don’t give different speeches to different audiences, all right?” Romney said. “I gave them the same speech. When I mentioned I am going to get rid of Obamacare, they weren’t happy. . . . That’s okay. I want people to know what I stand for, and if I don’t stand for what they want, go vote for someone else. That’s just fine.”

Obama is not addressing the NAACP convention this year, although Vice President Biden is scheduled to speak to the group Thursday. The Obama campaign issued a statement arguing that Romney is “the wrong choice” for black families.

During the 2008 campaign, Republican nominee John McCain addressed the NAACP. Although President George W. Bush had declined invitations to speak during the first five years of his presidency, he accepted in 2006. In his speech that year, he lamented the Republican Party’s difficult relations with black voters, adding, “I understand that racism still lingers in America.”

On Wednesday, the Obama campaign responded to Romney’s remarks by issuing a statement saying that “African Americans can’t afford Romney Economics.”

It added: “At the NAACP today, leaders in the African American community recognized the devastating impact Mitt Romney’s policies would have on working families,” campaign spokesman Clo Ewing said in a statement. “He’d gut investments in education, energy, and infrastructure, and raise taxes on the middle class even as he gives $5 trillion in tax cuts weighted towards millionaires and billionaires. He’d put insurance companies back in charge, threatening the health of more than 30 million Americans who will gain coverage because of the Affordable Care Act. And he refused to use the opportunity today to finally lay out a plan for improving health care or education in this country.”

Romney — who met privately with NAACP leaders before his remarks — directly responded to attacks from the Democrats that he would help only the wealthiest Americans.

“The opposition charges that I and people in my party are running for office to help the rich,” he said. “Nonsense. The rich will do just fine whether I am elected or not. The president wants to make this a campaign about blaming the rich. I want to make this a campaign about helping the middle class.”