A few hours before Mitt Romney spoke to the Republican convention last night, his campaign did something clever. It’s normal procedure before a major speech is to release excerpts so the evening TV news shows can preview the address. The Romney team did so, only these excerpts were dull and uninteresting.

Perhaps it was unintentional, but the effect was to lower expectations about the speech. This was unnecessary. The speech turned out to the best written, best delivered, and most appealing that Romney has ever delivered, at least in my presence.

He passed the convention test impressively. His speech is likely to propel Romney and running mate Paul Ryan out of the convention with momentum and maybe even with a bounce in the polls.

And, at least tacitly, he laid down a challenge to President Obama that went something like this: “I’ve got a plan to stir the economy, create jobs, and halt America’s decline. Where’s yours?” If Obama fails to offer one at the Democratic convention next week in Charlotte, the whole country will be aware.

Romney has a knack for coming through in stressful political situations. In the primaries, he improved his skill as a debater when rival Republican candidates were attacking him in televised debates. His speeches got better. He became a better candidate. If he hadn’t, he probably wouldn’t have won the GOP nomination.

He followed the script for the convention flawlessly. He criticized Obama, but not harshly. Like other speakers, he suggested that voters had good reason to be excited by Obama in 2008. But the president had let them down by not following though on his promises of progress on the economy. So as actor Clint Eastwood, a surprise speaker, said, “When somebody doesn’t do the job, you’ve got to let them go.”

Romney and his advisers believe these 2008 Obama voters, disappointed in the Obama presidency, are coming their way.  And Romney and his allies don’t want to do or say anything that might stop the former Obama enthusiasts from becoming Romney voters in 2012.  What might? Suggesting they were dumb to back Obama in the first place or demonizing or dissing the president that many of them still like personally.

It’s a risky strategy. Who knows what might prompt these voters to reverse course and go back to Obama? But polls show that millions of voters are deeply disillusioned about Obama and are Romney’s for the taking, if he doesn’t somehow alienate them.

Romney was most effective when he defended free markets and success in business. He accused Obama of “attacking success.” But in America, “we celebrate success. We don’t apologize success.”

This tack clashes with advice given to Romney months ago that he shouldn’t rely too heavily on his own career at Bain Capital as the centerpiece of his candidacy. He has, from all appearances, spurned that advice. His Bain years are central to his claim on the presidency.

He noted that, in 2008, Obama vowed to stop the rise in ocean levels and heal the earth. His goal is simpler, he said. “My promise is to help you and your family.”

Romney has now passed three tests—winning the nomination, picking a running mate who strengthens the ticket, and delivering a strong acceptance speech at the Republican convention. 

Romney has two final tests. The first is to campaign in a way that makes his election possible. The other is to hold his own in three televised debates with Obama. If successful at these final tests, he’ll be the next president.