A collaboration announced by Iowa Gov. Terry Branstad and Nebraska Gov. Dave Heineman on Friday will help create a bigger economic development pie for both states, officials said. Advance Southwest Iowa, a recently established public-private partnership of the city of Council Bluffs, Council Bluffs Chamber of Commerce, Iowa West Foundation, Pottawattamie County and the Western Iowa Development Association, formally joined the Greater Omaha Economic Development Partnership on Friday.  David Brown, president and CEO of the Greater Omaha Chamber, said the multicounty coalition “allows us to better leverage our region’s many assets and offer our prospective companies and clients a wider range of business, talent and investment options.” Advance Southwest Iowa also announced it has hired Mike Dellinger, vice president of economic development for the Council Bluffs Area Chamber of Commerce, to serve as its executive director.