Did Mitt Romney make the economic sale at the Republican National Convention? Did he convince people who are living at the margin or unemployed and discouraged that he has the answers to the economy? Frankly, I don’t think so.

I don’t understand why he didn’t talk about his 20 percent across-the-board personal tax cut plan, which would help the middle class enormously. He never mentioned it and he went into no detail on his business tax cut plan.

This plan is terrific for competition and global investment. He talked about a jobs tour. I frankly have no idea what a “jobs tour” is. I do know that 23 million Americans need jobs. I don’t know that they need a president on a jobs tour to inspect them.

It concerns me that in the economic zone, he didn’t make the sale to the independents, so-called Reagan Democrats, or to Clinton Democrats. I didn’t hear anything new. I didn’t hear anything specific, and it troubles me. I do think he helped himself enormously with his biographical narrative. He came off as a humble, grateful man.

Again, on the economic front I don’t think he made the sale; I don’t think he convinced the independent voters and I don’t think he’s going in the right direction on tax policy.

I think he needs to be more specific. It’s not about big business — it’s really about small business. And guess what? Small businesses pay the personal tax rate — the LLCs and the S-corps. That is another reason why I don’t understand why he doesn’t talk about the 20 percent tax cut. It helps small businesses and it contrasts with Obama, who wants to raise taxes on those people. I didn’t hear any contrast Thursday night, except a passage on success. The best line from an economic standpoint was: “In America, we celebrate success, we don’t apologize for success.” That is a great line, but I wish he had drawn more contrast with President Obama.

Sen. Marco Rubio’s introduction of Romney was one of the most brilliant speeches I have heard in a long time. Freedom was his key point. America is about freedom — economic freedom, political freedom, religious freedom, and faith. It was just utterly brilliant and the guy is an absolute Republican superstar.

Larry Kudlow is the host of CNBC’s “The Kudlow Report.”