Higher-income voters are narrowly supporting Democratic presidential nominee Hillary Clinton in another sign of how the 2016 presidential race is fracturing traditional voting blocs.
In a two-way contest, Clinton beats Republican Donald Trump 46 percent to 42 percent among likely voters with annual household incomes of $100,000 or more, the latest Purple Slice online poll for Bloomberg Politics shows.
The findings may sound an alarm for Trump because they show he's failing, at least so far, to dominate among a group of voters who historically have supported Republicans, including Mitt Romney in 2012. In that election, the group made up 28 percent of the electorate and backed Romney over President Barack Obama by 10 percentage points, exit polls show.
Since 1996, the Republican presidential nominee has won or tied among voters with annual household incomes of $100,000 or more, according to a compilation of exit polls by the Roper Center for Public Opinion Research at Cornell University. Republicans also won the top-earning groups publicly identified by the Roper Center in the 1976-1992 elections.
Higher-income voters do pick Trump over Clinton as the candidate they think would be best for their own investments, 45 percent to 36 percent. Among those who say Trump would be better for their holdings, 17 percent aren't supporting him. The poll's overall margin of error is plus or minus 4 percentage points, and is higher in subgroups like those.
"While he trails in the vote, Trump has advantages on economic and investment issues that matter to these higher-income voters," said pollster Doug Usher of the Washington-based Purple Strategies, who directed the survey. "His campaign's detours have put him on weaker ground overall. Closing the gap will depend on bringing the conversation back to jobs, trade, and the economy."
As is the case with other demographic groups, these voters give both nominees high negative ratings. Trump is viewed favorably by 36 percent, while 42 percent view Clinton favorably.
Higher-income voters give Clinton the overwhelming edge, 57 percent to 18 percent, on which candidate has been more transparent about sharing personal tax and health records with the public.
A plurality of 43 percent say it's very important that a presidential candidate make their tax returns public, while 42 percent say that about health history.
Among those backing Trump in the two-way race, just 19 percent say it's very important for a candidate to share their tax returns, while 45 percent say that of health history.
More than two-thirds, 71 percent, say the public's need for information about personal records such as health history and tax returns are more important than a candidate's right to privacy.
"Voters want more openness from their candidates, including health and tax records," Usher said. "It's going to be difficult for Trump to win the debate over releasing his taxes."
The survey was conducted Sept. 16-19, using a nationally representative opt-in panel of 600 respondents. It's the latest in a series commissioned by Bloomberg Politics on key slices of the electorate. The last survey, earlier this month, found Trump decisively winning white voters who don't have more than a high-school education.