Marco Rubio is bright, promising and charismatic. He’s got the Tea Party behind him and is the GOP candidate in his race for U.S. Senate … Why on Earth does he seem to be losing ground to Charlie Crist?

Simply put, the problem is that the Tea Party does not have political legs.

Bottom line, the answer to Rubio’s falling poll numbers has to do with independents, moderate Republicans and the huge swathe of people in Florida who are not extreme. Many of these people might be attracted to aspects of the Tea Party Movement, but the closer we get to actually voting for someone, the more likely they are to see Tea Party affiliation as a real negative. After all, we saw the Tea Party in another form almost two decades ago: its name was H. Ross Perot.

Folks, the squeaky wheel of activist conservatism and American populism might be getting the grease (i.e., a lot of media attention) right now, but when election time comes the buzz and passion of a new movement will matter less than appealing to the widest group of voters possible with the most credible candidate possible.

Fact is, Crist is perceived as being reasonable; Rubio is in danger of being perceived as too doctrinaire and unpredictable because of his outsider status. And in Florida, as in the rest of America, reasonableness and predictability almost always win over ideology.

Rubio seems to know this and has been careful to distance himself from the Tea Party label. Months ago, he said: “When you talk about the Tea Party, remember, I'm a Republican." But he also knows that it was his outside, populist status and his appeal to a vocal conservative base that has gotten him as far as he is right now. He can’t distance himself too much or he will lose their support as well and be seen to as backing away from his principles.

Rubio really is in a bind. But it’s a bind that’s shared by the Republican Party.

There’s a big lesson in this for Republicans looking for a reshaping of government in their favor this November. You simply can’t rely on the Tea Party. The most passionate, most vocal and most media-covered portion of the electorate will not win you the office. At the end of the day, a politician’s Target Market has to include independents and moderates and these voters will go for the candidate who is likeable and least extreme. Conservatism might go a lot farther in November, if it remembers the middle and doesn’t go too far right now.

And, remember, things are always easier when you keep marketing and branding in mind.

John Tantillo is a marketing and branding expert and president of the Marketing Department of America who markets his own services as The Marketing Doctor. He is a frequent contributor to the Fox Forum and the author of a new book "People Buy Brands, Not Companies."

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