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When it comes to U.S. presidential politics, lose Wall Street and you've lost the election.

Goodbye, Mitt.

It's over.

I know, I know. Many of you are going to call me liberal patsy, a mouthpiece for President Barack Obama. You're going to say I'm in the tank, a Democratic hack. Blah, blah, blah.

Whatever. You can disagree with me, but you can't argue with facts, and you can't dispute history. If it were the other way around, I'd call it as such.

The fact is, Romney is behind.

And history shows that, as a presidential election nears, Wall Street -- represented by the securities, banking, insurance and real-estate industries -- tends to go with a winner.

This doesn't mean that Romney, who made his career in private equity at Bain Capital, and Paul Ryan, who once championed turning a portion of our Social Security taxes over to personal investment accounts, aren't more ideologically in line with the financial industry. They are.

It doesn't mean that investors who support fiscally conservative principles have abandoned Romney in favor of Obama. They haven't.

What it does mean is that Romney continues to trail in key races. He's behind by at least five points in the critical swing states of Ohio, Florida and Virginia, according to a new round of polls. Wall Street wants to hedge its bets, buy some influence and be on the winning side. So, it has to make a choice: Support the loser or the winner.

Wall Street always goes with a winner.

It happened in 1996, 2000 and 2008. Presidents Clinton, Bush and Obama all saw a rush in contributions just before the election, according to Federal Election Commission data.

The closest to an exception to the rule was in 2004 when Democratic nominee John Kerry started seeing an increase in contributions from Wall Street in the final few weeks before the election. The reason? A tight race with an uncertain outcome. And, even so, President Bush was still outraising Kerry 2 to 1. It had been 3 to 1.

This year is shaping up to be similar. Romney has raised $28.6 million from finance, insurance and real-estate donors. Obama has raised $12.2 million through Aug. 21. But there's a lot of chatter about how the gap has narrowed since then.

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