Billionaire Donald J. Trump, an early presidential favorite among tea party activists, has a highly unusual history of political contributions for a prospective Republican candidate: He has given most of his money to the other side.

The real estate mogul and “Celebrity Apprentice” host has made more than $1.3 million in donations over the years to candidates nationwide, with 54 percent of the money going to Democrats, according to a Washington Post analysis of state and federal disclosure records.

Recipients include Senate Majority Leader Harry M. Reid (Nev.), former Pennsylvania governor Edward G. Rendell, and Rahm Emanuel, a former aide to President Obama who received $50,000 from Trump during his recent run to become Chicago’s mayor, records show. Many of the contributions have been concentrated in New York, Florida and other states where Trump has substantial real estate and casino interests.

The donations provide another view into the odd political spectacle surrounding Trump, who may be the most unlikely of possible GOP presidential hopefuls in an already eclectic field. Although candidates such as Mitt Romney and Tim Pawlenty have spent years carefully crafting and plotting a White House run, the tycoon and fixture of the New York tabloids has leapt onto the scene with loud proclamations and surprisingly strong poll numbers among likely Republican voters.

The iconoclastic developer and television personality is attempting to appeal to social conservatives, even with a record of failed marriages and earlier statements in favor of abortion rights. His attacks on Obama have focused on conspiracy theories about the president’s birth in Hawaii that make many Republican leaders nervous. And Trump is considering a run for the nomination in an increasingly conservative Republican Party, despite years of donations to prominent Democrats.

None of which has stopped him from forging ahead with a potential candidacy, including a scheduled trip on Wednesday to the early primary state of New Hampshire.

The Democratic recipients of Trump’s donations make up what looks like a Republican enemies list, including former senator Hillary Rodham Clinton (N.Y.), Sen. John F. Kerry (Mass.), Rep. Charles B. Rangel (N.Y.), Sen. Charles E. Schumer (N.Y.) and the late liberal lion Edward M. Kennedy (Mass.).

The biggest recipient of all has been the Democratic Senate Campaign Committee of New York, which has taken in more than $125,000 from Trump and his companies. Overall, Trump has given nearly $600,000 to New York state campaigns, with more than two-thirds going to Democrats.

His representatives did not respond to requests for comment Tuesday. But Trump said in a recent interview that he had relatively few Republican options in an overwhelmingly blue state.

“Everyone’s Democratic,” he told Fox News in an interview about his potential candidacy. “So what am I going to do — contribute to Republicans? One thing: I’m not stupid. Am I going to contribute to Republicans for my whole life when they get heat when they run against some Democrat and the most they can get is 1 percent of the vote?”

His Democratic generosity is hardly confined to New York, however. Trump has given more than $250,000 to federal candidates and campaigns, including more than $100,000 to the party’s House and Senate campaign committees. He donated $10,400 to Reid, including for his 2010 battle with Sharron Angle, the GOP nominee and tea party favorite.

Ron Bonjean, a GOP consultant and former Capitol Hill aide, said that “it will be hard for him to spin his way out of direct campaign contributions” to Reid and other Democrats.

“In a Republican primary, it shows where your loyalty lies,” said Bonjean, who has not signed on with a GOP presidential candidate. “He may be giving this money to Democrats because it helps his business, but it will be a big deal to Republican primary voters.”

While favoring Democrats, Trump has donated more than $600,000 to Republicans as well, including Sen. John McCain (Ariz.), the party’s 2008 presidential nominee, whom Trump first supported in 1998.

He gave $95,000 to the Republican Governors Association for its record-breaking electoral push in 2010, and he has donated more than $80,000 to the three national GOP political committees in the past two decades. Individual Republicans supported by Trump include former congressman Tom DeLay (Tex.), former House speaker Newt Gingrich (Ga.) and former senator George Allen (Va.).

The data collected by The Post for this article does not include donations to outside interest groups. Last year, for instance, Trump gave $50,000 to American Crossroads, which supported Republican candidates in the midterm elections.

GOP political consultant Alex Castellanos said Trump’s contribution pattern is similar to the approach of many business leaders and corporations that divide their donations between the two parties. But to get through a Republican primary season, he added, “it doesn’t help to have that record.”

One of Trump’s biggest Democratic beneficiaries was Rendell, who received $32,000 from the mogul during his 2002 primary and general election campaigns to become Pennsylvania’s governor. Rendell, who favors abortion rights, was challenged in the Democratic primary by Bob Casey Jr., who opposes abortion.

When he considered a run for president in 2000 as a Reform Party candidate, Trump said he supported abortion rights. But he said last week that he now opposes the procedure except in cases of rape or incest or when the mother’s health is at risk.

In Pennsylvania, Rendell favored allowing slots gambling, and Trump waged a long and ultimately fruitless battle to secure a casino license in the state after the practice was legalized. He publicly lashed out at Rendell when an independent gaming board rejected the license application, calling Pennsylvania “a little too political of a state for me.”

The tycoon benefited from a Rendell decision to lift a moratorium on water development rights in Philadelphia, allowing a planned Trump Tower project to proceed. The luxury development has since been put on hold amid the economic downturn.

Rendell did not respond to a telephone message seeking comment Tuesday.

Former congressman Thomas M. Davis III (Va.), who served as chairman of the National Republican Congressional Committee, said Trump’s close ties to some Democrats would be “a huge obstacle, but it’s not insurmountable.” Trump, he added, would not be running as a “purity” candidate.

“Republicans are looking for a savior,” Davis said. “Here’s a guy who has succeeded outside politics and articulates the right vision. Sometimes that works. . . . It’s a long shot, but it’s not out of the bounds of possibility.”