If the American people want a choice between the two major party candidates for president, they saw significant differences last night. As opposed to the first debate, when the two rivals made a point of agreeing with each other, their second encounter drew contrasts. Beyond the meta-analysis about President Obama becoming more aggressive and the viral memes about Governor Romney's "binders full of women," one real take-away for these elusive undecided voters is the candidates' distance when it comes to fixing the economy: One has a plan and one doesn't.

Whether you like President Obama's plan, you can at least acknowledge that he has one he stands by. It involves a clear direction for taxes, with an emphasis on asking millionaires to pay their fair share. The president returned to that theme again and again, contrasting it with the reductions in taxes he has already passed for 98 percent of Americans. He can point to his successes - the rescue of the auto industry, the slow but gradual job growth - and promise to continue that course… and to amplify those efforts with the energy that comes from a second election.

His plan also accounts for how a host of other issues affect the financial security of regular Americans. Reining in medical costs and creating a more navigable healthcare market saves families money. Supporting student loans and changing the rules for how loans get repaid helps young Americans start their careers. From ensuring access to contraception to tackling credit card charges to enforcing better gas mileage for automobiles, President Obama made the case for an array of tools, small and large, the government can bring to the service of Americans everywhere.

Not everyone likes that plan. You might feel that the Obama Administration moved too slow in its first term. You might not believe in his track record. You might share the blame with Republican obstructionism but not see how that will change in a second term. You might not want more of the same.

But it was Romney who offered the most compelling endorsement of the incumbent when he said last night: "I can tell you that if you are to elect President Obama, you know what you're going to get."

By contrast, if you elect Romney, you have no idea what you're going to get.

No idea because his position keeps shifting. Punctuating a career of policy pivots, he has now fully backed away from the tax cuts for the 1 percent that has been part of his plan. He keeps side-stepping which elements of Obamacare he supports. Yesterday, he even claimed he supports access to contraception - a change from his position in the primary. You just don't know what Mitt will do because he's a moving target.

Furthermore, you have no idea what you're going to get because when it comes to details, he refuses to divulge any. He and Ryan almost boast about the fact that they don't have details worked out for how to pay for their tax cuts (in marked contrast with Ryan's extremely detailed and unpopular budget proposals in the past). When asked about job creation, Romney's answer was to trust him - he has a plan. When asked about stimulating the economy, his answer was to trust him - he has a plan. But it must be a secret plan because in his opportunity to share it with a national audience, he demurred.

And when the moderator pressed him on what would happen if the numbers shouldn't add up, his answer: "Well of course they add up."

Trust me, he's saying. But he won't say why.

The Obama campaign throughout has hoped to make this election a referendum on Mitt Romney - an unlikable, out-of-touch poster boy for the 1 percent. However, last night may make this November a referendum on the president - because he's the only one with a track record to run on and a plan he stands by.

You may decide whether you like what he's done in four years. You may choose based on whether you trust his commitment to the next four. But to reiterate Romney's words: "If you are to elect President Obama, you know what you're going to get."

And what will you get if you elect Mitt? Based on last night's performance, it's less likely the American people will find out.