Leading Republicans in a key Florida battleground have condemned Mitt Romney's campaign for writing off African American voters and attitudes toward minorities that they say have cost the party crucial support.

Art Wood, chairman of the Republican party in Hillsborough County, a diverse area of about one million people and one of the most heavily contested regions of the state, said his party's presidential candidate failed to even try to win over black voters.

"Romney did a really poor job with minorities. That was my greatest disappointment. You'd go on to his website and he'd have a column for outreach. You clicked on that and there was Catholics for Romney, Democrats for Romney, fishermen for Romney. You never saw blacks or African Americans for Romney until four weeks ago," Wood said.

"I think it's the big frigging smart guys at the top who think they know how to run a campaign, and they probably just wrote off the African American vote. Romney did a really poor job with the African Americans. They're in many ways like Hispanics. They favour traditional marriage, they go to church regularly, they're suffering worse from unemployment."

Wood was backed by a Republican contender for the US Congress in the area, EJ Otero, who is not even including his party affiliation on his election posters and literature because he thinks it will harm his chances.

"I think it's true but not only with the Romney campaign. That's a problem with the Republican party as a whole, and not just with African Americans. Hispanics, too. The Republican party has written off African Americans and Hispanics for the past 20 years and it needs to change," he said.

Otero, a former air force colonel who served in Iraq and is of Cuban descent, said part of his party's problem is how it discusses issues that are important to minorities such as immigration and welfare.

"I do believe we've got to get off the emotional argument of: the border, the border, the border. We need to control the border so white slavery stops and narco trafficking. But when it comes to the people, we're talking about community," he said. "There's also this myth that all poor people want here is handouts. They don't. All they want is the jobs they used to have."

Otero acknowledged that he has distanced himself from his own party. "I put my ideas. Nowhere in there does it say I'm a Republican. That's not helpful," he said.

African American and Latino voters waiting outside the C Blythe Andrews library in Tampa to cast their ballot in early voting said Republican attitudes towards the less well off, and even "fear" of a Romney presidency, is driving people in the area to the polls.

"This is a serious election," said Tonya Lewis who runs a charity, Children With A Vision, to help underprivileged young people in school. "There's been so much negativity from the Republicans. Mitt Romney scares the hell out of me. Romney can't relate to the people, he has no connection to the people. People are really afraid because if you get somebody whose worth millions of dollars, how can they know?"

Betty Reed, a Democratic party representative in the Florida legislature, said that turnout for early voting in the area is so high that she was arranging buses to move people to less busy polling stations.

"Voters in this area support the president but they're turning out to keep Romney out. His campaign played a big role. He went to the NAACP meeting and he talked about how he wanted to get rid of Planned Parenthood, things that are good for poor people. He didn't talk about what he would do for us," she said. "Race is also a part of it. There's more than one issue but we know some people did not want Obama to be successful as president and we know why."

Vivien Warren, who was brought from Cuba to the US as a child, was among those at the library voting for Obama. She said that the Republican-controlled Florida legislature's cutting in half of the number of days early voting, along with attempts to introduce new photo identification requirements at polling places that were struck down by a federal court as discriminatory, also drove people to vote.

"There's been a lot of talk among people about voter suppression. People are angry. How dare they? They're trying to prevent us from voting," she said.

"People are also angry that Romney and the Republicans have been disrespectful of the office of the president. The way Romney talked to him at the debate. People think that's about race. They don't want a black person in the White House."

The legislature's removal of the last Sunday before the general election as an early voting day – a day when many African Americans went to the polls after church – mobilised religious leaders to launch a campaign, Souls to the Polls, to get black people to vote the previous Sunday instead. Vote monitors say it was successful and that turnout in minority districts will at least match that of 2008.