Who could blame Sen. Barack Obama’s (Ill.) camp for thinking the Democratic convention would finally end its candidate’s consistent underperformance in the polls? After all, how can you go wrong with a stage right out of a Hollywood back lot and a “green” convention full of Hollywood types for the college crowd? How can you not get a big bounce with the Clintons finally bringing the party together?

[IMGCAP(1)]How can a convention so hip and cool not do in the corny Republican crowd? And how can the biggest spectacle in political history not blow Sen. John McCain (R-Ariz.) out of the water once and for all?

The answer is simple. When it comes to picking their presidents, the American people want steak, not sizzle. McCain delivered a convention packed with a newfound energy and excitement following his choice of Alaska Gov. Sarah Palin to be his running mate and boffo speeches by former New York Mayor Rudy Giuliani (R) and former Sen. Fred Thompson (R-Tenn.) that brought down the house.

And McCain closed it out by giving voters the steak they were looking for — an acceptance speech with substance. He moved viewers by telling them in a very personal way of his time as a prisoner of war and how it changed him. But he also offered up his vision for the future — one of reform and change — and ended with a little sizzle of his own, bringing the delegates to their feet with one of the best oratorical closes in recent political memory.

Despite all the pre-convention hype, when the confetti had settled, it was McCain’s “Country First” convention that won the ratings battle with 38.9 million viewers, beating out Obama’s 38.4 million. Palin blew Sen. Joseph Biden out of the park with 37.2 million viewers for her acceptance speech in contrast to the Delaware Democrat’s 24 million.

But the more important numbers are the post-convention polls. Initially, Obama got a small bounce after his convention, but it was a short-lived gain that masked what has been a tightening over the summer. When McCain and GOP Congressional leaders moved to make energy a central economic issue, Democrats’ generic advantage began to shrink.

Last week, Republicans were positioned for a breakout and McCain led the charge, delivering a convention bounce the Obama people didn’t see coming. On Sunday, the USA Today/Gallup Poll had McCain at 50 percent to 46 percent over Obama, an 11-point gain. But more significantly, it showed McCain has closed the gap on the key question of who can better handle the economy.

Before the conventions, Obama held a 19-point advantage on this most important of issues, but the new poll shows it has dropped to 3 points, within the margin of error. Gallup’s daily tracking, which showed Obama with an 8-point lead just after his convention, now puts McCain in the lead by 5.

By midweek, more polls will give us a better feel for the size and staying power of the bounce, but it’s already clear that “Country First” beat the “Colossus of Colorado.”

McCain’s surprise choice of Palin excited the base in a way that no other choice would have done while, at the same time, connecting with a number of key voter groups: married women with children, independents and blue-collar Democrats.

Reinforcing this connection with swing voters were McCain’s and Palin’s speeches.

McCain, in vintage form, smartly and honestly first took on his party: “We lost [the people’s] trust, when we valued our power over our principles. … We’re going to change that.”

Palin staked out her ground as a reformer with an electrifying speech that showed she represents a new generation of conservatives who don’t fit the narrow-minded, out-of-touch mold Democrats and the media have tried to cast on the GOP. Voters saw a changing of the GOP guard in St. Paul, Minn., and they liked it.

The post-convention environment finds Obama and his campaign on the defensive. By raising concerns about Palin’s experience, Obama, Biden and their bidders only raised more questions about Obama’s experience.

The over-the-top criticism of Palin by Democrats, left-wing bloggers and the media also put the Obama campaign on the defensive. After his campaign’s initial condescending statement in response to the Palin announcement, Obama and Biden tried to back away and take the high road. But thanks to continuing ill-advised comments by his surrogates, left-wing bloggers and even Oprah Winfrey, damage to his image has been done.

Obviously frustrated, Obama’s campaign has even complained that McCain’s convention slogan was an attack an his patriotism, thus conjuring up the Carly Simon line, “You’re so vain, you probably think this song is about you.” “Country First” had nothing to do with Obama and everything to do with McCain and his lifetime of service — the central theme repeated throughout the convention.

It’s a long time until November. Palin has hurdles to leap, and the Obama camp will pull out all the stops. The candidates will have to survive the debates, and voters will be watching closely. The conventions proved that.

But with the end of the convention period, the McCain campaign has a big and well-deserved win under its belt.

David Winston is president of the Winston Group, a Republican polling firm.