TRENTON -- As the New Jersey governor's race barrels into its final stretch, new figures show Democratic nominee Phil Murphy has maintained his dramatic fundraising advantage over Republican opponent Kim Guadagno.

Meanwhile, more than $8 million in spending from independent groups has poured into the race in recent weeks, as the Nov. 7 election to succeed Gov. Chris Christie draws closer, according to the numbers released Tuesday by the New Jersey Election Law Enforcement Commission.

Murphy, who has a double-digit lead in the polls, has raised and spent more than three times as much as Guadagno and boasts more than three times as much cash on hand, according to the figures from from ELEC, the state's election watchdog agency.

Murphy, a former U.S. ambassador to Germany and ex-Goldman Sachs banking executive, raised $13.3 million, spent $9.8 million, and had $3.5 million in reserve as of Oct. 24.

Guadagno, Christie's lieutenant governor, raised $3.9 million, spent $3.3 million, and had a reserve of $632,169.

Both candidates are taking part in the state's matching funds program, in which gubernatorial candidates receive $2 in public money for every $1 they raise on their own.

ELEC reports that spending by independent groups has soared from $2.6 million to $10.6 million in the last three weeks alone.

Counting the spending from all candidates and all independent groups, there has been roughly $23.8 doled out on the race so far, according to ELEC.

New Jersey is one of only two states with governor's races this year, along with Virginia.

"As a result, the race has attracted significant spending from Washington, D.C.-area groups, including both the Democratic and Republican Governors Associations and national unions," said Jeff Brindle, ELEC's Executive Director.

Brindle added that the "heavy bombardment" of independent spending continues a trend that began in the 2009 governor's race, when Christie was elected.

"This type of spending is now a fixture in both gubernatorial and legislative campaigns," Brindle said, suggesting that the state Legislature approve legislation that ELEC recommends to require more disclosure by independent groups.

The biggest independent spender: Committee to Build the Economy, a super PAC which has spent $6.1 million to benefit Murphy.

The Democratic Governors Association has spent $2.9 million on candidates and parties throughout New Jersey, while the Republican Governors Association has spent $2 million.

There are also five third-party and independent candidates running in the governor's race. Of those contenders, Green Party nominee Seth Kaper-Dale has raised the most ($96,316), followed by independent Gina Genovese ($52,046), and Libertarian Peter Rohrman ($7,765).

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