As of January 2012 ...
Obama - 2/3
Romney - 7/5
Paul - 25/1
Gingrich - 30/1
Santorum - 35/1
Huntsman - 50 /1
Since Perry is running behind a candidate that isn't even running (Hillary), I'll stop typing there.
Interesting is that Paul has moved up into 3rd place. Opensecrets.org reports that the Wall Street money is splitting so far between Romney and Obama. With Obama still the obvious favorite, they don't want to abandon him. And they appear to be succeeding in pushing Romney to the top of the Republican table. Thus creating what Wall Street always love is a non-contest between two politicians they've already bought.
The fly in this ointment is Ron Paul. He isn't bought by Wall Street, he opposes the wars, and he'd fight to restore civil liberties. He's not my perfect candidate, but he's in the race and running strong and has positioned himself as the one viable choice in these big party nomination fights that would end Wall Street rule in America.
If you oppose the wars. If you don't like having candidates who've been bought by Wall Street running everything. If you actually think the Bill of Rights is a good thing and we need to get back to honoring and respecting the deal that formed this government and approved this Constitution, then the only choice is to do everything you can to support Ron Paul. Vote for him if you can. Volunteer for him, help make phone calls, do whatever else you can do to support him too.
Its Obama, Romney and Paul. Two of the three represent no real change. One does represent change. And failing to support the candidate that does represent change is also a vote that you like things right now just fine and don't want any change from our endlessly expanding wars and rule by Wall Street all enforced by an ever growing surveillance state.