Rep. Tom Latham (R) announced Friday that he will run in Iowa’s new 3rd district against Rep. Leonard Boswell (D), setting up the first incumbent-versus-incumbent matchup of the post-redistricting cycle. The move spares Latham from facing Rep. Steve King in a GOP primary.

“I have never let map boundaries block the great honor I have felt in representing the interests of all Iowans in the United States Congress,” Latham, who has been in Congress for nine terms, said in a statement. “After thoughtful discussions with my family, friends and supporters over the past two weeks, I am writing to share with you my decision that I will be a candidate for Congress in Iowa’s new Third Congressional District in 2012.”

Iowa will lose one House seat this cycle due to population declines, and the new Congressional map, which is expected to pass next week, moves Latham into King’s district. Instead of running against his GOP colleague, Latham has opted to run against Boswell.

Boswell’s former 3rd district seat was competitive, although the eight-term Democrat has held it because Republicans frequently failed to find a good candidate to run against him. Nonetheless, in 2010, he won re-election by a slim 4-point margin.

But Boswell’s new district includes more Republican voters, making him an even more susceptible target for the GOP. Boswell has also made clear that he’s running again, telling reporters Friday morning that he’ll stick with the Des Moines-based district.

Minutes after Latham’s announcement, national Republicans were already touting his candidacy against Boswell.

“I applaud Tom’s decision to fight for job creation and opportunity for more Iowans by running for Iowa’s 3rd Congressional District,” National Republican Congressional Committee Chairman Pete Sessions (Texas) said in a statement. “Tom has the leadership, vision and Main Street America solutions to combat Democrats’ tax, borrow, and spend agenda that continues to discourage job creation in Iowa and across the nation.”

Latham will also kick off his campaign with more money in the bank than Boswell. At the end of the first quarter of this year, the Iowa Republican had $984,000 cash on hand, but Boswell had only $173,000.

The new Congressional map, which still requires the governor’s signature for final passage, roughly divides the state into quadrants, down from the five districts Iowa had for the past 10 years.

In addition to moving Latham and King into the same district, the new map also pits Democratic Reps. Dave Loebsack and Bruce Braley against each other. However, Loebsack has said already he will move out of the district instead of facing his Democratic colleague.