For his first four terms, Latham represented a district that stretched from Sioux City in the northwest all the way to Mason City on the other side of the state. The 2000 round of redistricting, however, significantly altered Iowa's congressional map. Latham's home in Alexander, along with most of the eastern third of his old district, was placed in the new 4th District in the north-central part of the state. This district was considered much more competitive than Latham's old district. For the 2008 elections, it had a Cook Partisan Voting Index of D+0.4, making it one of the most marginal districts in the nation. However, he was reelected four times from this district without much difficulty. This may be because he is the only Iowan on the powerful House Appropriations Committee.