Congressman Jesse Jackson Jr. pleaded guilty on Wednesday to embezzling $750,000 in campaign funds, capping a months-long circus — Jackson and his wife, who entered a guilty plea, spent thousands on pieces of Michael Jackson memorabilia, a limited-edition Rolex, and at least two cashmere capes — only to make room for another. Indeed, the special election to fill Jackson's seat on the south side of Chicago, scheduled for April 9, is something of a dual story of our times: A familiar story of city politics and corruption is giving way to a test of national gun-control politics turned local — and evaporating campaign-finance limits that may upend another election cycle beginning as soon as next week.

Lawyers

Jackson, who faces up to five years in prison when sentenced on June 28, resigned in November shortly after his re-election. He and his legal team have kept a low profile, but not too low a profile — he still endorsed Chicago Democratic fixture Robin Kelly, who is running to replace him. (Kelly is decidely pro-gun control — a key factor in the race. More on that below.) That's not to say the trial has severed Jackson's loyalty to Chicago, though. He approached one reporter in a D.C. courtroom Wednesday to express his remorse:

Guns

Here's where the special election gets interesting. Michael Bloomberg, the three-term mayor of New York City, has invested $2.5 million in a Super PAC called Independence USA, which is trying to steer the primary race away from Congresswoman Deborah Halvorson, a Democrat who is known for supporting expanded gun rights. (The same Super PAC also attacked Toi Hutchinson, an Illinois state senator also known for supporting gun rights, before she dropped out of the race on Tuesday.) This has led some (well, Deborah Halvorson) to accuse Bloomberg of trying to buy a Congressional seat. Here's how Bloomberg defended his investment:

"It's just an outrage, and the public ... should stand up," he told reporters in New York. "I'm part of the public. I happen to have some money, and that's what I'm going to do with my money – try to get us some sensible gun laws."

Now, Bloomberg's involvement does look a bit funny — he's the mayor of New York! — but it's of a piece with his strategy from November 2012, when he targeted several national races where pro-gun candidates had a leg up on opponents who advocated for stricter gun laws. Bloomberg is staunchly anti-gun, and his Mayors Against Illegal Guns coalition has become — along with Gabby Giffords — one of the national faces of gun-control lobbying, and financing, since the Newtown shooting. And it's totally understandable that a seat representing a portion of Chicago, which continues to struggle with gun violence — President Obama was there last week — would hold a symbolic weight.

Money

Still, the sudden influence of Bloomberg's wealth is striking. Almost by himself, Bloomberg has made this single election one of the most expensive Congressional campaigns of this cycle — and we haven't even seen this race's primary, which is scheduled for February 26. Counting Bloomberg's massive spend, the race has accumulated about $3 million total from out-of-state sources, placing it in the top 10 percent of 2012 Congressional races

This is, of course, a testament to the power of so-called Super PACs, which grew out of the 2010 Supreme Court decision Citizens United vs. Federal Election Commission. Such groups successfully flooded many comparatively small elections (like this one) with tons of capital. Now, this isn't the first Congressional race to fall under the influence of Super PACs, which rose to prominence amidst the 2010 mid-terms. But those who manage Super PACs know more now than they did in 2010, and will likely view this early election as a bellwether of their 2014 strategy — not just in how to marshal which funds, and where, but how to defend doing so, as Bloomberg is now. As the Center for Public Integrity put it,

The first congressional contest of the 2014 election cycle may be emblematic of a new norm in House races, where cash-flush super PACs and politically active nonprofit groups easily outspend candidates. And given the Illinois race and the GOP intra-party fights in 2012, spending won't be reserved for the general election, either.

And then there's the bigger picture: Bloomberg's strategy serves a vivid reminder of the odd consequences of letting wealthy individuals spend as much as they want to influence the country's political system. Why, after all, is Bloomberg — the current mayor of New York City — meddling in a Congressional election in the state of Illinois? That could be something to ponder as the Supreme Court decides whether to allow individual citizens to contribute as much as they want to candidates and parties of their choice. And it could be something for Republicans to grapple with as Democratic-aligned Super PACs plot to recapture a House majority and possibly strengthen the Democratic Party's grip on Senate supremacy — a strategy the GOP would be foolish to ignore.