Here is the latest Iowa news from The Associated Press at 3:38 a.m. CST

ANKENY, Iowa (AP) — With just one week left until the caucuses, the candidates’ Iowa organizations are more important than ever. Hundreds of staffers and volunteers have fanned out across the state, knocking on doors and making calls to ensure their candidate’s supporters turn out on caucus night. Bernie Sanders’ campaign is canvassing voters in unusual locations, like trailer parks and outside CVS pharmacies. Elizabeth Warren has had some of the most seasoned staffers organizing in Iowa since the spring, and she’s hoping they’ll help her make up for lost ground in the polls. Meanwhile, Joe Biden is facing questions about how robust his organization is in smaller counties around the state.

LINCOLN, Neb. (AP) — Four states along the Missouri River are joining forces to look for ways to avoid the kind of flooding that caused millions of dollars in damage last year. Nebraska, Iowa, Missouri and Kansas are pooling their money to pay for half of a $400,000 study with the U.S. Army Corps of Engineers to measure how much water flows down the Missouri River. State officials hope to present a united front to federal officials to gain more influence over how the river is managed after devastating floods in 2011 and 2019.

DES MOINES, Iowa (AP) — The fight for the Democratic presidential nomination is raging across Iowa as the party’s leading candidates and their allies deliver losing arguments that focus on who’s best positioned to defeat President Donald Trump. Self-described democratic socialist Bernie Sanders has emerged as a central figure in the electability debate. New polls show him gaining strength just eight days before Iowa’s first-in-the-nation presidential caucuses on Feb. 3. That strength is causing concern among his more moderate Democratic rivals. They fear he’s too radical to beat Trump in November.

WATERLOO, Iowa (AP) — Organizers of an emergency warming shelter in Waterloo have been given more time to operate while they search for another location that meets local fire codes. The Courier reports that Waterloo Fire Chief Pat Treloar has given the shelter inside the Jubilee United Methodist Church Freedom Center until Jan. 31. The overnight shelter opened Jan. 6 to provide a safe haven from freezing temperatures to the homeless. But organizers were told it would have to close on Jan. 21 after an inspection found the space didn’t have a sprinkler system. The state fire marshal granted an extension after learning organizers had found possible alternatives.