Democrat Bill Richardson has offered a farm package that limits payments to giant operations, restricts large meatpackers and gives incentives for alternative energy production.
Speaking at a farm near Council Bluffs, Richardson also coupled his plan with a call for civility in the race for the party's presidential nomination.
"Let's keep the mud where it belongs," Richardson said in remarks prepared for delivery Tuesday afternoon. "We cannot build America up by tearing each other down."
Richardson's package, some of which he'd discussed previously, calls for a $250,000 cap on farm subsidy payments and a ban on meatpackers owning livestock, a move designed to improve competition for farmers' products. The package also proposes new tax incentives for development of renewable fuels, and other incentives to expand broadband access in rural areas.
In addition, Richardson said he would increase funding for conservation programs and invest more in wind energy and other new technologies. As part of that effort, he would spend more on educating people for careers involving such technologies.
"I have a 10- to 12-year crash program that moves us away from carbon-based to renewable energy sources," said Richardson, a former U.S. energy secretary and two-term governor of New Mexico.
Although his speech was focused on farming and the environment, Richardson also called upon his Democratic rivals to refrain from an increasingly bitter debate in the weeks leading up to Iowa's precinct caucuses on Jan. 3.
"That is not what we need and I call on my colleagues to stop it," said Richardson. "Winning an election is not worth sacrificing our principles."
Although candidates must note their differences, Richardson said they should stick to policy matters.
"Unfortunately, in Washington today there's too much negativity, negativity over health care, negativity over immigration," he said.
In his policy package, Richardson sought to blend together farm incentives with alternative energy proposals he has discussed on the campaign trail. Those plans address wind energy, ethanol production and biodiesel fuels.
Richardson set ambitious goals, including cutting greenhouse gas emissions by 30 percent by 2020 and reducing dependence on foreign oil by 50 percent over the same period. He would offer tax credits for production of ethanol and other alternative energy options, including biofuels, wind and solar.
He also pledged to support "an alternative energy infrastructure" that would include flex-fuel and plug-in pumps at gas stations.
Richardson said he would couple his farm proposals with an aggressive effort to help small, rural communities.
"I know we can do all of these things because as I've traveled the country it has become clear to me that Americans are ready to act," said Richardson. "What our country needs now is real leadership."