Senators including Mary Landrieu, John McCain and Pat Toomey are holding events.
The elections "are referendums on the candidates running," said Debbie Wasserman Schultz.
The Florida Republican's operation raised a combined $1.1 million in 2014’s first quarter.
She's played a major role in Tea Party elections for the past five years.
Former business exec Curt Clawson leads pack of Republicans vying to fill Trey Radel's seat.
Senate hopefuls battled ahead of the May 20 Georgia Senate primary.
Alexander Bolton 04/19/14 12:31 PM EDT
She has raised more than $2.3 million for Senate Democratic candidates this election cycle.
Georgia candidate David Perdue has pushed for an end to government waste.
The ad is the FWD.us's first major foray into the 2014 elections.
A spokesman for the secretary said Friday she is not considering a run for the Senate.