If political cartoonists cheered the arrival of Donald Trump on the campaign trail, investigative journalists are rubbing their hands over Newt Gingrich’s recently announced candidacy.

Gingrich’s penchant for testing ethics boundaries may not be his biggest problem as he seeks the GOP presidential nomination. Some contend that the former House speaker’s undisciplined, pedantic style will damage him the most.

Still, as the first speaker ever sanctioned by his colleagues, Gingrich carries unusually heavy ethics baggage. Although he claims to have changed and learned from his mistakes, he presides over a complex network of controversial groups that is remarkably similar to the one that got him in hot water almost 20 years ago.

For those who don’t remember GOPAC, let’s rewind the videotape to 1994 (retro reference intentional). Gingrich had just helped his GOP colleagues take over the House, but he faced a Federal Election Commission lawsuit and complaints from state ethics officials in Georgia and Wisconsin.

The target of these complaints was GOPAC, which Gingrich called an “educational institution,” but which looked more like a leadership political action committee. GOPAC was at the heart of an interlocking network of pro-Gingrich groups; it collected big money from influential donors, most of it in secret. (Sound familiar?) In his GOPAC fundraising letters, Gingrich offered donors the chance to help him “draft the Republican legislative agenda,” and credited the group with helping elect 41 of that year’s 48 House GOP freshmen.

The House Ethics Committee eventually punished Gingrich with a $300,000 sanction, which was euphemistically called a “cost assessment,” faulting him for failing to ensure that his nonprofits didn’t run afoul of the Internal Revenue Service and for giving investigators false information. The IRS ultimately cleared Gingrich-associated groups of any tax violations, and he and his allies claimed vindication.

Fast-forward to 2011. Gingrich presides over a complex network of political, consulting, philanthropic, and communications groups that aggressively promote him. The biggest is his "527" group American Solutions Winning the Future, which, according to the Center for Responsive Politics, raised and spent more than $28 million in the 2010 election cycle, making it by far the most lucrative 527 out there.

Like GOPAC, American Solutions has attracted its share of controversy. It is heavily underwritten by casino and fossil-fuel money. Gingrich has also taken heat for receiving generous consulting fees from the ethanol industry. Reporters are going to enjoy digging into his network of groups and itemizing every penny that comes from ethanol, oil, coal, and other special-interest donors.

Gingrich “is going to encounter increased scrutiny, and there is a clear potential downside of the complexity of Newt, Inc.,” said Bill Connelly, a professor at Washington and Lee University. “And that is partly because of his history.”

Big differences exist between Gingrich’s current public-relations and political empire and his GOPAC operation, of course. The most important is that Gingrich has, until now, not been holding or seeking public office, insulating him from conflict-of-interest allegations, noted John J. Pitney Jr., a politics professor at Claremont McKenna College.

Republican primary voters are not likely to care much about arcane political-money controversies. And Gingrich, having pioneered the use of secretive, irregular committees for political purposes, is now in good company – thanks, in part, to the Citizens United v. Federal Election Commission ruling that partly deregulated elections.

“In the early ’90s, that model was extremely unusual, and it stuck out,” said Pitney. “Twenty years later, it’s just the way politics is done.”

Gingrich undoubtedly has scrupulous lawyers, and his allies have maintained that all of his activities are on the up-and-up. Moreover, his 527 group, for one, has helped him build an impressive donor base. Although American Solutions Winning the Future spends a lot on overhead, the group has cultivated hundreds of thousands of small donors, a pool that any presidential campaign would envy.

Even so, Gingrich’s official candidacy changes everything. Though campaign fundraising is turning into something of a free-for-all, the ban on soft (unregulated) money remains in place. Gingrich may no longer raise and spend money through his American Solutions 527, said Paul S. Ryan, associate legal counsel with the Campaign Legal Center. And Gingrich’s reputation and history are bound to earn him special scrutiny.

“Everything about Newt is a double-edged sword,” Pitney observed. “On the one hand, his network of organizations has helped sustain his credibility as a spokesperson on public policy, including health issues, and has kept him in the public eye. On the other hand, any time large amounts of money are changing hands, watchdog groups are going to get interested, and start raising questions.”

Gingrich’s ethics issues may prove to be the least of his worries. His three marriages will also come up. His tendencies to speak before thinking and to play the professor will not help. Gingrich’s strengths as a coach and team leader are “not the same skill set you need to be a unifying figure as president of the United States,” his former chief of staff, Frank Gregorsky noted. Gingrich may well be a new man. But when it comes to political money, the new Newt Gingrich looks an awful lot like the old one.

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