Today, Iowa Democratic Rep. Dave Loebsack announced he won't seek reelection in 2020, presenting Republicans with a good pickup opportunity next fall. Loebsack, a former college professor, had cultivated an outsider image that helped him to defeat longtime GOP Rep. Jim Leach in a huge 2006 upset and survive multiple GOP waves in a Republican-trending seat. Loebsack's exit virtually assures a competitive race.

This southeastern Iowa district, which includes Davenport and Iowa City as well as much more conservative rural counties, voted for Barack Obama 56 percent to 43 percent in 2012 but swung to President Trump 49 percent to 44 percent in 2016. Both parties have deep benches of local officeholders, and each party's top vote-getter would need at least 35 percent of the vote in next year's primary to avoid a convention.

Loebsack is one of 31 House Democrats sitting in districts carried by Trump in 2016, and one of just four remaining House Democrats who defeated Republican incumbents in the wave of 2006 (the others are Reps. Jerry McNerney, Joe Courtney and John Yarmuth). Republicans would likely need to capture this seat to win the House back in 2020. The seat moves from the Likely Democratic column to the Toss Up column.

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