Planned Parenthood’s political arm on Thursday will release a series of ads targeting four Republican senators in tough re-election races who have supported defunding the health services nonprofit.

The ads attack Sen. Richard Burr (R-N.C.), Sen. Kelly Ayotte (R-N.H.), Rep. Joe Heck (R-Nev.) and Sen. Pat Toomey (R-Pa.) for their record on women’s health issues. All four targets of Planned Parenthood Votes and Planned Parenthood Action Fund’s campaign face strong challenges from Democrats.

“Each one of these Republican Senate candidates has voted to defund Planned Parenthood and staked out positions that threaten millions of women across this country,” Deirdre Schifeling, the executive director of Planned Parenthood Votes, said in a press release. “Not only is this agenda dangerous, but it is incredibly unpopular.”

Gilbert Carrasquillo via Getty Images Planned Parenthood's political arm has launched a $2 million ad campaign targeting Republican Senate candidates who voted to defund the organization.

Republicans have routinely politicized Planned Parenthood and its federal funding, especially after an anti-abortion organization last year released edited videos purporting to show Planned Parenthood representatives selling fetal parts. GOP lawmakers launched a series of investigations that ultimately turned up no evidence of wrongdoing ― except by the anti-abortion group.

One of the new ads targets Heck’s repeated votes to defund Planned Parenthood, accusing him of “putting women’s lives at risk” and calling him “a dangerous politician.” It will run on TV in both English and Spanish.

Digital ads focus on the Republican senators’ efforts to restrict abortion and birth control access, and their opposition to equal pay for women.

The ads are part of Planned Parenthood Votes and Planned Parenthood Action Fund’s $30 million political campaign this year, which it says is the largest in its history. The group has launched a website informing voters about candidates’ records on abortion access and reproductive rights, and has staff and volunteers in the battleground states of North Carolina, New Hampshire, Nevada, Ohio and Pennsylvania.

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