On the final full day of campaigning before the Iowa caucuses, former Mass. Gov. Mitt Romney appeared at a series of rallies Monday. His rallies grew in size and enthusiasm over the course of the day. Romney holds a slim lead over Texas Congressman Ron Paul and former Pennsylvania Senator Rick Santorum.

Over the weekend, the multi-billion dollar subsidy for ethanol expired. It had been in place for more than 30 years but Congress let it expire. Bruce Babcock, the Cargill endowed chair of energy economics at Iowa State University, talks to Linda Wertheimer about the effects of the subsidy expiring on the ethanol industry and consumers.

The voting in the Iowa GOP caucuses begins Tuesday night. On the last day before the caucuses, Republican presidential candidates campaigned across the state Monday. Their goal was the same — motivating supporters to leave their homes on a cold evening, go to their precinct meeting places and vote.

Police have arrested a German national living in Hollywood and charged him in connection with more than 50 arson fires that destroyed parked cars and scorched buildings in Los Angeles. Harry Brukhart, 24, was arrested early Monday morning, and is being held without bail.

Much has been made of the unusual volatility of the GOP race this year, with candidates taking turns in the front-runner spot in Iowa. But with more outside money and a reliance on social media, the run-up to this election season's Iowa caucuses has been different in other ways as well.

An explosion set off a series of shootings by a U.S. Marine squad in Haditha in one of the war's more controversial incidents. The military trial starts this week for the squad's leader, the only Marine still facing charges in the killings. Others were acquitted or had the charges against them dropped.

The new year brings an increase in the minimum wage in a number of places around the country, including Washington state, which now boasts the nation's highest statewide rate: $9.04 an hour. But the increase has rekindled an old debate over whether minimum wages make sense — especially at a time of high unemployment.