The honeymoon Sarah Palin has been enjoying with American voters -- ever since John McCain's surprise announcement that he was putting her on the Republican ticket -- is now officially over. And I'm writing this before tonight's vice presidential debate, I should note.

It cannot be denied that her nomination as vice presidential running mate to John McCain certainly had an effect on the race. It shook the race up. And for a short period, it looked like an absolutely brilliant and stunning political gamble by McCain to inject some much-needed vitality into his campaign. McCain's poll numbers rose, while Obama's fell. Palin herself enjoyed high approval numbers in the polls. She gave a rousing speech at the Republican Convention, and a lot of Democrats got very worried indeed.

It turns out they needn't have bothered. Sarah Palin is now seen with increasing frequency as a drag on the ticket for McCain, if not an outright punchline for a joke. And not just by the lefty blogosphere, either. Serious right-wing pundits have been weighing in for the past week on whether Palin should step down from the ticket. And that's from her own party.

The tide turned because of Katie Couric on CBS. Because Katie committed an act of journalism. Somehow she got one of the only exclusive interviews with Palin, perhaps because the McCain campaign thought she'd be some sort of softball interviewer. She proved them wrong.

Not only did Couric ask Palin some substantive questions, she followed up when Palin refused to answer them. And when Palin was obviously floundering around looking for something to say, Couric zeroed in on the exact issue Palin seemed not to understand. Again and again.

I have to say, this type of journalistic excellence has been sorely missing on the campaign trail in the networks' evening news broadcasts, and it came from an unlikely direction... but I have to give Couric full credit where credit is due.

Since Palin's debut on the CBS news, McCain's poll numbers have tanked. Now, McCain himself may have made a crucial mistake last week with his "handling" of the economy. Looking back, we may pinpoint last Wednesday as the McCain's final and fatal self-inflicted wound. When McCain announced he was "suspending" his campaign, that he was dropping out of the first debate, and (for good measure) that he was blowing off an appearance on David Letterman, his campaign may have gone into a nosedive it will never recover from. Time will tell.

But it's not just McCain's poll numbers that are tanking, it is also Sarah Palin's own poll numbers. Now, some of this is undoubtedly due to McCain's floundering around last week, but not all. When America saw Sarah Palin unable to answer Katie Couric's basic questions, doubt settled in. And since CBS is doling these interviews out piece by piece over a full week, the effect has been cumulative and growing.

Palin's support among independents crumbled. As did her support among women in general. She still enjoys some Republican support, but not as much as last week, and the trendline is down. People from her own party are publicly suggesting she step down from the ticket to improve McCain's chances of winning, which certainly wasn't happening last week either.

So, even before tonight's debate, I am officially pronouncing the "honeymoon" American voters appeared to be having with the Governor of Alaska over and done. She was a "breath of fresh air" on the political scene for approximately one month. Then reality sank in -- her running mate is 72 years old, and she may indeed become president if elected with McCain.

And that started worrying a lot of people, and outright scaring some of them.

Because it was never about her daughter's baby. Or her baby. Or her lipstick. Or her beauty-queen past. Or moose hunting. Or any of the other superficial nonsense certain parts of the media love to obsess over. It's always been fundamentally a job interview -- for the second-most important position in American government. To the giant "hiring committee" that is the electorate -- and all the folksiness in the world can't seem to cover up how empty she seems to be at her very core.

Now, she could turn out to have a great debate performance tonight. Stranger things have happened. But if she answers even once with the deer-in-the-headlights stumbling we saw on CBS, then this race may be all but over.

And even if she does do well and recover somewhat in the polls, the honeymoon is still going to be over. Because with the economy crumbling about us, voters are more interested in competence than glitz at this point, and I don't expect that to change at all until Election Day.

[Note: I am writing this before tonight's vice presidential debate. For my debate reactions, you'll have to wait for tomorrow's column. I apologize in advance if you're coming here post-debate, but feel free to have at it in the comments, as usual.]

-- Chris Weigant