Iowa GOP Rep. Rod Blum has consistently been underestimated, and in 2016 he won reelection 54 percent to 46 percent while President Trump carried the district 48 percent to 45 percent. But on Tuesday, the Ethics Committee announced that it was investigating him following a February Associated Press report that he had failed to disclose his role in an internet marketing company.

Blum says the failure to disclose was a simple administrative oversight, but Democrats are already cuing ads calling him part of "the swamp." His bigger vulnerability is that he's a conservative Republican sitting in a labor-heavy district with a strong Democratic heritage (it voted for Barack Obama by double digits twice). Today, both parties' polling depicts him as an underdog for reelection in November.

In June, 29-year-old Dubuque state Rep. Abby Finkenauer won the Democratic primary with 67 percent. The graduate of Drake University describes herself as an "Iowa tough" daughter of a union pipefitter welder and a schoolteacher and has outraised the incumbent $1.8 million to $1.7 million with the help of EMILY's List. Finkenauer would be

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