It could be very dangerous for Obama if Mitt Romney clears a basic competence threshold with voters — that is, if voters accept that his success in the private sector shows he possesses basic leadership qualities and a talent for turning around troubled enterprises that can magically be applied to a whole country.

Central to that argument is the premise of Romney’s whole candidacy: That you can run American like a corporation, and that Romney’s experience has left him with an understanding of the economy that automatically translates into an ability to create jobs as a public official.

Today the campaign will be fought around that idea.

With Obama set to visit Ohio, Romney is out with a new Op ed in the Cleveland Plain Dealer that states the message clearly, even stating explicitly that the federal government is an “enterprise” that can be turned around like a business:

Mr. President, forgive me for being blunt, but when it comes to economic affairs, you’re out of your depth. Unlike you, I am not a career politician. Unlike you, I’ve spent more than two decades working in the private sector, starting new businesses and turning around failing ones. Undoing the damage you’ve done will be a daunting challenge. But I’ve learned a thing or two about how government policies can kill private investment and stifle job creation and I have a plan to get government out of the way...

I have spent much of my life in business, turning around troubled enterprises. I can do the same for the most troubled of all enterprises: our federal government.

Of course, despite Romney’s claim that he isn’t a “career politician,” he has, in fact, been a public official — he was Governor of Massachusetts, a fact that goes oddly unmentioned in today’s Ohio Op ed. And the DNC is out with a new Web video today offering the response to Romney’s argument above — it shows footage of Rick Santorum brutally attacking Romney for presiding over a state that ranked 47th out of 50th in job creation.

Santorum’s punchline: “If Mitt Romney’s an economic heavyweight, we’re in trouble”:

As the above video shows, the effort to spotlight Romney’s job creation record in Massachusetts will be key to the effort to undermine Romney’s aura of basic competence and the whole premise of his candidacy. This isn’t the last we’re seeing of this Santorum footage.

By the way: Note Romney’s description of his “plan to get government out of the way” and his repeated vow to “unleash” America’s “potential.” That’s Romney’s plan, in a nutshell: Get government out of the way and allow an unshackled private sector to shower prosperity and opportunity on everyone. As I argued here yesterday, it all turns on whether voters ask themselves this question, and how they answer it: What is Romney really offering here?

* Disappointing jobs numbers: Of course, monthly jobs numbers like these could make voters so hungry for an alternative that they accept Romney’s argument:

Nonfarm payroll employment rose by 115,000 in April, and the unemployment rate was little changed at 8.1 percent, the U.S. Bureau of Labor Statistics reported today. Employment increased in professional and business services, retail trade, and health care, but declined in transportation and warehousing.

However, the last two months were revised upwards: “The change in total nonfarm payroll employment for February was revised from +240,000 to +259,000, and the change for March was revised from 120,000 to +154,000.

* Romney’s narrow path to the presidency: Dan Balz and Philip Rucker have a good overview of the electoral map and the hurdles Romney faces on the road to 270. Here’s the whole ball game:

Romney’s team acknowledges that any realistic course to 270 starts with winning back three historically Republican states that Obama won in 2008 — Indiana, North Carolina and Virginia — and believes that changing demographics in Virginia present a challenge.

After that, Romney must play take-away with the Democrats in a number of other states that the Obama campaign flipped to its column four years ago.

* Why Obama is winning in Virginia: Chris Cillizza ferrets out a great nugget from the new Post poll that explains why Obama is leading there by seven:

A majority of Virginians — 52 percent — say that “Barack Obama’s views on most issues are just about right” as compared to 37 percent who say the same of Romney’s views. Among electorally critical independents, 52 percent say Obama’s views were about right as opposed to just 34 percent who say the same of Romney.

As Cillizza notes, the fact that Obama is such a good ideological fit for Virginia and its changing demographics is a high hurdle for Romney, particularly since this state is emerging as pivotal to the outcome (see previous item).

* A note on one of Romney’s leading talking points: David Corn gets economic experts to take a crack at verifying Romney’s claim that once Obamacare fully kicks in, government will “control half the economy.”

As Corn notes, media figures continue to politely look the other way while Romney makes statements that are basically too outlandish to even evaulate.

* What if the mandate preserves, rather than destroys, liberty? Jonathan Cohn and David Strauss make an interesting case: A decision to uphold the individual mandate would actually strike a blow for, rather than against, individual liberty in the modern age, and would be perfectly consistent with the Constitution and the spirit of capitalism.

* What inequality hath wrought: Paul Krugman on why inequality itself is a leading cause of the GOP unwillingness to embrace Keynsian solutions to fixing the economy, and the polarization and paralysis that has followed. By the way, Krugman’s new book, “End this Depression Now!” is now available.

* Demographic deep dive of the day: National Journal’s lead story today goes deep into how demographic changes in many of the country’s fastest-growing counties are allowing Obama and Dems to contest suburban areas that have been long out of Dems’ reach and are becoming more and more important to the electoral map.

* Flashback of the day: With Darrell Issa threatening to hold Attorney General Eric Holder in contempt of Congress over the “fast and furious” probe, Michael McAuliff unearths video of the very same Darrell Issa stalking off the House floor when Dems held Bush officials in contempt in 2008.

* And, yes, Obama has been vetted: Jonathan Bernstein has a nice response to one of the big storylines of the moment, that David Maraniss’ new book will undermine the Obama “narrative.” No matter how many times people assert otherwise, Obama has been fully vetted already, and no revelations will change the public’s now-firm conclusion about who he is and how he will continue to govern.

What else?