ATLANTA (AP) — Republicans had millions of reasons to recoil when Donald Trump said a judge of Mexican descent couldn't handle his lawsuit fairly.
Namely, the millions of voters it takes to win the White House.
Specifically, the minority voters who powered President Barack Obama into office, as well as the college-educated and suburban white voters who weren't enthusiastic about Trump during the GOP primary.
Republican strategists and donors say Trump's latest foray into racial politics frustrates the party's efforts to win over those voters. As the Republican National Committee acknowledged after Mitt Romney's 2012 loss to Obama, it will be almost impossible for a Republican to win competitive battleground states without them.
"It's not that Donald Trump has created a demographic problem for Republicans," said Chip Lake, a Republican campaign consultant from Georgia. "That's existed for a long time. But he's highlighted the problem."
Trump set off a firestorm when he alleged U.S. District Judge Gonzalo Curiel, whose parents were born in Mexico, had mistreated him because of Trump's pledge to build a wall on the U.S.-Mexico border. Curiel is hearing a case involving the defunct Trump University.
"He's a Mexican," Trump said, and a "hater of Donald Trump."
Curiel, a former federal prosecutor, was born in Indiana to parents who came from Mexico. He has not responded to Trump's attack, and Trump's legal team has not sought his removal from the case.
House Speaker Paul Ryan called the remarks "racist," while South Carolina Sen. Lindsey Graham labeled them "un-American." Illinois Republican Sen. Mark Kirk withdrew his backing for Trump's candidacy and Gov. Scott Walker of Wisconsin, an important state for Trump, tempered his support, calling on Trump to renounce his comments.
Trump has refused. On Tuesday, he told Fox News that Republicans angry at him should "get over it."
Lake, who has run campaigns across the South, said Trump's attacks on Curiel are simply the latest component of a caustic appeal that won't work for a general electorate expected to top 130 million — or roughly 10 times the number of votes Trump received in GOP primaries.
Republican donor Fred Malek noted that many voters are just beginning to pay close attention to Trump and presumptive Democratic nominee Hillary Clinton.
"Moderate and conservative Republicans want to come around behind our nominee," said Malek, chairman of a fundraising group backing Republican congressional candidates. "And they are halted in their tracks when they see comments like this."
Indeed, the electoral math is daunting for Republicans even without Trump. As America becomes more diverse, the percentage of white voters is declining.
Mitt Romney won about 59 percent of the white vote over Obama in 2012. That essentially mirrored George H.W. Bush's 60-40 advantage among whites over Michael Dukakis in 1988. But in Bush's victory, whites cast 85 percent of presidential ballots, helping the 41st president carry 41 states and run up 426 electoral votes.
In 2012, whites accounted for just 72 percent of presidential votes, yielding just 24 states and 206 electoral votes for Romney, who won just 27 percent of the Latino vote and 6 percent of African-Americans.
So in 24 years, an essentially level performance among white voters netted 220 fewer Electoral College votes (81.5 percent of the necessary 270 required to win). It's a landscape that helped Obama sweep Florida, Virginia and Colorado, along with the Rust Belt and Great Lakes region.
Meanwhile, population growth among Hispanics and other minorities suggests the white share of the electorate could dip to 70 percent in November.
That leaves Republican and Democratic consultants alike projecting Trump would need about two out of three white votes nationally to tip the scales in enough battleground states — a level no national candidate has reached since Ronald Reagan's 1984 re-election landslide.
Trump argues that he is a movement candidate who can generate strong white support but also attract more African-Americans and Latinos than GOP nominees typically get. He points to record turnout for GOP primaries.
Yet an Associated Press-Gfk Poll in April, as Trump barreled toward the nomination, found seven out of 10 voters viewed him negatively. Those findings spanned gender, ideological, racial and educational lines. Trump's 13 million-plus primary votes — and the 30 million-or-so total GOP primary ballots cast — are dwarfed by Obama's general election vote totals of 69.5 million and 65.9 million.
Making up the gap is virtually impossible, said Pennsylvania-based Republican consultant Ray Zabourney, if Trump alienates college-educated and other middle-class whites who populate suburbs around cities like Detroit, Cleveland, Philadelphia and Milwaukee.
Spending time ahead of the summer convention railing against a Hispanic judge "isn't helping you get a single vote from Wisconsin to Pennsylvania," Zabourney said. "And if it's not doing that, it's not helping win the presidency."
Beaumont reported from Des Moines, Iowa.
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