Mitt Romney still holds a commanding lead among likely Republican caucus-goers, but Fred Thompson is becoming a force to be reckoned with, according to the latest Des Moines Register poll. Read the full article at the preceding link.

Romney stays ahead with 29% as Thompson moves into second with 18% support. Huckabee (12%) and Giuliani (11%) battle for third as McCain draws only 7%, only slightly ahead of Tancredo's 5%, and insurgent Libertarian Ron Paul registers 4%.

The Real Clear Politics average of the most recent state polls shows Romney holding 25.8% over Giuliani's 15.8% and Thompson at 15.6%, Huckabee with 9.8% and McCain trailing with 8.6%.

Romney has spent heavily in Iowa and seems to be reaping the benefits. Thompson's surge of strength may be a natural result of his formal entry, but it still shows he can be a force in the state.

So, who can afford to lose Iowa? Giuliani was never expected to win the state, whose Republicans lean strongly to social conservatives. He can afford to lose, but a third or fourth place finish would weaken him if he continues to campaign actively. Thompson has only begun to build an organization there, but his expectations were always set higher for the southern states. McCain opposes subsidizing ethanol and skipped the state in 2000, so he started with two strikes.

Romney, though, lacks the strength of Giuliani or Thompson in many of the states which will vote by February 5th. He leads in New Hampshire now, but he needs a win in Iowa to maintain that lead and generate momentum for the following contests. Two early wins would establish his national credibility as a candidate and create strong "buzz." The free media such a result draws would be worth millions. That's Romney's whole strategy, in a nutshell, and it begins with Iowa. Win, and he's a player. Lose, and he could save himself some money by dropping out.

Huckabee needs to finish second or a very close third at least just to stay alive. If he fails to do that well, the money won't be there to continue. But should he pull it off, he will skip New Hampshire and head straight for South Carolina and Florida to play on his home court. Huckabee success would threaten Thompson most of all, but also further diminish McCain's slim hopes.

Barring a shockingly good showing in Iowa, Tancredo is gone. Ron Paul has nothing but "upside" there, and goes on no matter what his results.