TRENTON - A Democratic gubernatorial candidate wants state election officials to punish the race's wealthy Democratic front-runner over political groups he set up before officially entering the race, but Phil Murphy's campaign says the complaint filed Thursday is without merit.

Jim Johnson, a former Treasury official in President Bill Clinton's administration, requested that the Election Law Enforcement Commission investigate Murphy, a former U.S. ambassador to Germany in President Barack Obama's administration.

Johnson's campaign alleges that the social-welfare and political groups called New Start New Jersey and New Way for New Jersey that Murphy set up before officially entering the race in May constituted exploratory committees.

Murphy's campaign said he would seek the complaint's dismissal and called it baseless.

Johnson "is wasting taxpayers' money in forcing ELEC to look into allegations that he, as an attorney, knows don't pass the laugh test," said Murphy spokeswoman Julie Rogninsky.

Johnson's complaint, obtained by the Associated Press, contends that Murphy's eventual gubernatorial campaign benefited from those groups' raising about $5 million in contributions

"His own statements make it clear that Phil Murphy viewed these nonprofits as a way to get a head start on his run for governor," Johnson said.

Johnson alleges that Murphy avoided disclosing some contributors and expenditures and that he skirted the close scrutiny that comes with declaring a gubernatorial run so early. But Murphy's campaign calls that claim baseless and provided an addendum to their Internal Revenue Service filings showing that Murphy disclosed that he donated the $1 million to New Start New Jersey. That group isn't required by law to disclose donors.

IRS documents show the second group, New Way for New Jersey, disclosed - as required - the donors that gave it about $4 million in 2015 and 2016.

The penalty, if the commission decides to investigate and finds a violation, is a fine of up to $8,600, according to state election officials. New Jersey law considers candidates who are "testing the waters" to be candidates and subject to filing and transparency requirements.

Murphy, who has lent $10 million to his campaign, has been leading in public polls ahead of the June 6 primaries.

Johnson has trailed in the single digits but has qualified for matching funds, having received nearly $900,000 so far, according to election records.

Johnson earlier this year asked Murphy to agree to a $15 million spending cap in the primary, where Murphy has racked up key endorsements and used millions of his own cash to surge to a dominant position. Murphy had no response to Johnson's request.

Experts say it's not uncommon for candidates to hold off announcing a run while they consider if it's something they want to do. In New Jersey, winning requires lining up local endorsements and party infrastructure, which takes time, said Matthew Hale, an associate professor of political science at Seton Hall University.

"Candidates want to do all of this before they are official, not necessarily because they are doing anything illegal or unethical, but because it is easier to do without paperwork," Hale said.