WESTMINSTER >> Bob Dole thought he could win California with a “fishhook” strategy. George W. Bush came armed with $15 million. John McCain was bullish, too. They all lost.

Donald Trump’s prediction that he can capture the biggest prize in the November presidential election, the state’s 55 electoral votes, rubs up against a dismal history for Republicans over a generation. The names on the ballot have changed, but the outcome has been the same — double-digit wins for Democrats since 1992.

Here’s Trump’s challenge: unite Republicans while finding millions of new supporters in a state where Democrats hold every statewide office and both chambers of the Legislature. They also have a 3.1 million edge in voters, a number equal to the population of Iowa.

In 1996, Dole was brimming with confidence about his chances against then-President Bill Clinton. Dole’s campaign aimed to drive up vote margins in Republican-friendly communities down the state’s interior spine, then up through coastal counties in the south, roughly in the shape of a fishhook. Money and staff poured in. Dole’s running mate, Jack Kemp, had special credentials: He grew up in Los Angeles.

It wasn’t even close. Clinton ran up a 51-to-38 percent win.

“Since 1996, the California electorate has swung even more to the left,” said Ken Khachigian, a former chief speechwriter in the Reagan White House who ran Dole’s campaign in the state.

“Five months out, it’s political malpractice to rule out any possibility,” Khachigian added. But a Republican win in California “comes as close as anything to an exception.”

The home turf of Richard Nixon and Ronald Reagan, California was once Republican in presidential elections. But pronounced demographic shifts, particularly a boom in the Hispanic population, have transformed the state.

The number of Hispanics, blacks and Asian-Americans combined has outnumbered whites in California since 1998, and Latinos alone now outnumber the white population. Most of the new voters are Democrats or independents who tend to vote like them.

Trump is looking to expand his support at a time when he already faces challenges with Hispanics and women. That stems in part from his promise to build a wall along the border with Mexico and his verbal attacks on U.S. District Judge Gonzalo Curiel, who is hearing a lawsuit against Trump University. Trump also has criticized New Mexico Gov. Susana Martinez, who heads the Republican Governors Association.

Richard Hoyt, a registered independent from Westminster, in Orange County, is the kind of voter Trump needs to pull his way. But the 64-year-old retired engineer says he’s leaning toward Clinton, in part because of Trump’s statements about Curiel and the judge’s family’s Mexican roots.

Hoyt said he would give Trump a “zero for his mannerisms” and added: “I can’t imagine how all of the sudden he’s going to change.”

Part of Trump’s challenge is simple arithmetic.

In California’s June 7 primary, the billionaire businessman ran essentially unopposed, pulling in about 1.5 million votes, or about 75 percent of the total. Ted Cruz and John Kasich were still on the ballot, though they earlier dropped out of the race.

Analysists predict 14 million people are likely to vote in November.

To win, Trump would need a heroic turnout from the state’s 4.9 million Republicans, while finding 2 million or more swing voters to get near a majority. Indeed, some of those swing voters could be lurking in counties where Republican candidates have outperformed the party’s registration numbers.

But there are more than 8 million Democrats, and the state’s 4.2 million independents — about 1 in 4 voters — tilt Democratic.

Trump’s state director, Tim Clark, emphasized that Trump’s supporters are strongly motivated in a year when many voters are looking for candidates from beyond Washington. As an outsider, Trump could appeal to a vast pool of dormant voters soured on status quo politics, Clark said.

“Elections are won by those who show up, and those who show up are those motivated by their candidate,” Clark added.

The last significant push by a Republican to win California was in 2000, when Bush was backed by $15 million, then lost to Democrat Al Gore by 12 points. In 2004, Bush’s campaign vowed to compete in California, but the campaign effectively shut down in early autumn.

McCain, the 2008 GOP nominee against Barack Obama, boasted about competing in California, but he lost by 24 points. Mitt Romney suffered a 23-point loss to Obama in 2012.

Aside from her registration advantage, Clinton also has a formidable get-out-the-vote operation. The campaign made 2 million phone calls in the final days before the state primary. Trump has no comparable organization. An energized Hispanic turnout is likely, favoring Clinton, who also carried the state in the 2008 Democratic presidential primary.

Republicans remain healthy in pockets of California, including parts of the vast farm belt and the so-called Inland Empire running east and north of Los Angeles. But party registration overall has withered to 27 percent of the state total, compared with 45 percent for Democrats.

Independents now outnumber Republicans in nearly two dozen of the state’s 53 congressional districts.

Former Gov. Pete Wilson, a Ted Cruz supporter who now backs Trump, is the last Republican to win a U.S. Senate race in the state, in 1988.

He acknowledges the steep climb Trump faces, but said in an unpredictable political year Trump could make inroads with independents and voters wary of Clinton. At the minimum, he said Trump could win a tactical victory if he forces Democrats to compete on their own ground.

Democrats “will have to respond and they will have to spend time and money here,” he said.