The freshman lawmaker is fixing filings that overstated her fundraising totals.
He beat back conservative writer Michael Flynn to take the nomination.
Clinton is hopeful Dems can narrow the gap. Pelosi says they can win the majority.
Obama and Pelosi will attend a fundraiser at green activist Tom Steyer's home.
Kathleen Matthews is running for the Maryland seat left open by Rep. Chris Van Hollen.
The election was to replace former Rep. Alan Nunnelee, who died of brain cancer.
Mario Trujillo 05/30/15 11:39 AM EDT
Turnout could be higher in the Ro Khanna-Rep. Mike Honda rematch in California.
Scott Wong 05/28/15 12:22 PM EDT
Scott Wong 05/27/15 04:24 PM EDT
The poll of GOP primary voters in the district shows Paul Babeu with the early edge.
Rep. Frank Guinta allegedly took more than $350,000 in illegal campaign donations.