TRENTON -- Phil Murphy, the early Democratic favorite in this year's race for New Jersey governor, has donated at least $1.15 million to state and local Democratic organizations and candidates since 2001, according to an NJ Advance Media analysis of campaign finance records.

More than 40 percent of that money -- about $466,000 -- was shelled out over the past three years, a period during which Murphy, a millionaire former Goldman Sachs banking executive, took steps toward launching his campaign to succeed Republican Chris Christie as governor.

The donations came from Murphy, his wife Tammy, jointly from the couple, or from his gubernatorial campaign, according to the analysis, the most in-depth look so far at how much Murphy has given to in-state causes.

The last time a statewide candidate in New Jersey has donated at such a level was when then-U.S. Sen. Jon Corzine, also a Democrat and a former Goldman Sachs executive, gave millions in his run-up to being elected governor in 2005. From 1999 to 2005, Corzine and his family donated $5.1 million to Democratic organizations in the state.

Murphy's opponents say he is using his money to gain influence among the state's Democratic leaders whose support is crucial to winning the party's nomination for governor. Murphy, also a former U.S. ambassador to Germany, has been endorsed by all 21 county Democratic Party chairs in the state.

Bill Schluter, a Republican former state senator who helped write the state's pay-to-play laws, said Murphy appears to be "using the Corzine process."

"It's a sad commentary about New Jersey politics," Schluter said. "He's getting the endorsements. ... It just rolls along, and that's all you need: the party line in the big counties."

But Murphy, 59, who has touted himself as a political outsider who will battle special-interest politics in Trenton, strongly disagrees.

He emphasizes that he has been "raising money one dollar at a time" and has spent months meeting with voters and political leaders across the state to build a grassroots campaign.

"We're campaigning in the streets, one vote at a time," Murphy, who has never held elected office, told NJ Advance Media. "We're out trying to scour not just the state but the country and the world for one policy idea at a time. We're building this from the bottom up."

His campaign also stressed that Murphy was the finance chair of the Democratic National Committee from 2006 to 2009, a period when he worked with then-party chairman Howard Dean to focus on raising money in every state, not just party strongholds.

Now, the campaign said, Murphy is following a similar model in New Jersey, donating money at a local level to bolster Democrats throughout the state, especially in traditionally Republican-leaning areas like Hunterdon, Morris, Somerset, Sussex, and Warren counties.

Derek Roseman, a campaign spokesman, said the effort has paid off in places like Morris County, where Democrats picked up nine local elected seats last year.

"The goal is making sure Democrats here have the resources to win," Roseman said. "It's part of growing the party."

Political leaders and experts argue that while Corzine, who donated millions more than Murphy, simply "threw" money at the nomination, Murphy has been more involved.

"Corzine did not like gripping and grinning and shaking hands," said Matthew Hale, a political science professor at Seton Hall University. "And Murphy, to me, seems to love that. They're both rich. They both worked on Wall Street. But I think the similarities end there."

State Sen. Richard Codey (D-Essex), a former governor who was elbowed out of the 2005 gubernatorial race when Corzine dumped his millions in, said Murphy is "doing well because of his personality" -- not his money.

"When (Corzine) first ran, everybody called to get a job because the salaries he was paying were three or four times more than anybody else was paying," said Codey, who has endorsed Murphy. "Phil has street sense and knows how to relate to people."

Murphy's top opponents in the Democratic primary see it a different way. State Sen. Raymond Lesniak (D-Union) said he "wouldn't accuse him of buying the election because the election is not over, but it's an outrageous abuse of money that if successful is a real threat to having competitive elections."

The campaign of state Assemblyman John Wisniewski (D-Middlesex) accused Murphy of using "his Wall Street fortune to buy party bosses with hundreds of thousands of dollars in donations" and receive their endorsements in return.

The campaign of former U.S. Treasury official Jim Johnson said "no candidate should be able to use their millions to buy the top spot or exclusive rights to the word 'Democrat' on the ballot."

By comparison, Johnson gave $3,300 to in-state causes and candidates over the last 15 years; Lesniak $45,000; and Wisniewski and his wife $21,550.

Murphy and his wife have been prolific donors on a national scale for decades, contributing more than $2.2 million since 1999 to federal candidates including President Barack Obama, Democratic presidential candidate Hillary Clinton, and U.S. Sen. Al Franken of Minnesota.

That figure includes $172,000 to New Jersey federal campaigns, including every Democrat general election U.S. Senate candidate. Tammy Murphy also made a few donations to Republican New Jersey candidates Bob Franks, Diane Allen, and DeForest "Buster" Soaries.

In the first few years after the Murphys moved to New Jersey in 2000, the couple gave mostly to federal groups and candidates, making only a few state-based donations. They gave $50,000 to the state Democratic Party in 2002, $25,000 in 2004, $4,700 in 2006, and $10,000 in 2008.

In 2007, Murphy donated $2,600 to Codey's successful re-election bid to the state Senate and $2,600 to state Sen. Ellen Karcher's unsuccessful re-election bid. In 2008, he donated $3,000 to Corzine's gubernatorial re-election bid.

When he served as the nation's ambassador to Germany from 2009 to 2013 under Obama, Murphy made no donations in New Jersey.

But the contributions increased in 2014, shortly after he returned from Germany. Around that time, he was first mentioned as a possible gubernatorial candidate to succeed Christie, who is in the last year of his final term.

In 2014, Murphy and his wife each donated $37,000 -- the most allowed under state campaign-finance law -- to the Democratic Party in Bergen County, the most populous county in New Jersey. Murphy also gave $25,000 to the party in Middlesex County, the second most populous county.

His campaign noted that the money Murphy gave in Bergen helped Democrat James Tedesco beat Republican incumbent Kathleen Donovan that year to become county executive.

In 2015, Murphy and his wife donated $154,000 to Democratic parties across the state -- including $37,000 to both Middlesex and Passaic. And once again, they each gave $37,000 to Bergen.

The Murphys also contributed tens of thousands of dollars that year to individual candidates and party committees, at the federal, state, county, and even municipal levels.

Murphy, who has loaned his campaign at least $10 million of his own money, officially announced he was running for governor in May 2016. In the four months leading up to that, he donated $34,650 to Democratic organizations and candidates in New Jersey -- including $20,000 to the state party.

The only county parties that Murphy has not donated to are Camden, Cape May, Cumberland, Gloucester, and Salem -- all in the southern half of the state.

Murphy noted that most of his donations came before he was a candidate.

"I had no expectation of running for governor when I came back from representing our country in Germany," he said.

Ben Dworkin, director of the Rebovich Institute for New Jersey Politics at Rider University, stressed that campaigns in the state are expensive and "statewide candidates, regardless of who they are, are expected to help support the local and county organizations of their respective parties."

"And it's easier for someone with personal wealth to write checks," Dworkin said.

Initially, Murphy was expected to be locked in a close three-way race for the Democratic gubernatorial nod with state Senate President Stephen Sweeney (D-Gloucester) and Jersey City Mayor Steve Fulop.

But in September, Fulop announced he wasn't running and endorsed Murphy. Democratic county chairs began to coalesce around Murphy, and Sweeney said in October that he wouldn't run.

That month, NJ Advance Media detailed how Murphy won endorsements from a dozen county chairs by personally courting their support at diners and Italian restaurants across the state.

So far, Murphy has officially been endorsed by all 10 of the county Democratic organizations that have held their conventions to reward endorsed candidates with the best spot on the ballot: Atlantic, Bergen, Essex, Hunterdon, Middlesex, Monmouth, Ocean, Sussex, Union, and Warren counties. He has donated to all of them in recent years.

Lou Stellato, chairman of Bergen County's Democratic Party, noted that many county chairs were either leaning toward Fulop or Sweeney before that, while others were "keeping their powder dry."

Stellato said the idea the chairs picked Murphy because of his donations "doesn't meet the timeline of how it happened at all."

He said Murphy had to win a formal vote to take the Bergen party's convention last month. Murphy received 80 percent of the nearly 800 committee members who voted.

"It was not 12 people in a room making a decision," Stellato said. "These are rank-and-file people. They say he's a personable guy."

Added Hunterdon County Democratic Chairwoman Arlene Quinones-Perez: "He knows how to build our party across the state."

Matt Arco may be reached at marco@njadvancemedia.com. Follow him on Twitter @MatthewArco or on Facebook.

Brent Johnson may be reached at bjohnson@njadvancemedia.com. Follow him on Twitter @johnsb01. Find NJ.com Politics on Facebook.