Rep. Marsha BlackburnMarsha BlackburnTrump's Twitter lockout raises safeguard concerns Anti-pyramid scheme legislation is necessary to protect consumers from fraud Former Tennessee rep enters race for Corker's Senate seat MORE (R-Tenn.) on Friday penned an open letter to President Obama saying a new campaign ad that equates voting for Obama with a sexual act is offensive, and asked that the ad be removed.

"As a father of two beautiful girls, how could you possibly have allowed this to be aired?" Blackburn asked. "Did you approve this? Did someone on your campaign staff actually think this was a good idea?

"It is offensive, repulsive and should be removed immediately. It is beneath the dignity of the office you hold," Blackburn said.

Blackburn's letter is a reaction to an ad for Obama starring Lena Dunham, the creator of HBO TV show "Girls." In the ad, Dunham says her "first time" voting was for Obama, and suggests that other voters' "first times" be with him, too.

"My first time voting was amazing," she says. "First I was a girl, now I was a woman. I went to the polling station, I pulled back the curtain, I voted for Barack ObamaBarack Hussein ObamaOvernight Cybersecurity: What we learned from Carter Page's House Intel testimony | House to mark up foreign intel reform law | FBI can't access Texas shooter's phone | Sessions to testify at hearing amid Russia scrutiny Russian social media is the modern-day Trojan horse Trump records robo-call for Gillespie: He'll help 'make America great again' MORE."

"Mr. President, are you and your Democrat colleagues so focused on sex and reproductive rights that you really think that is the single motivator for women?" Blackburn asked in her letter. "Are you not aware that women in 2012 are focused on jobs, the economy, economic opportunity? Women are running companies, serving as the human resource director of companies and helping employees solve problems."

The "first time" Web video has drawn plenty of Republican criticism since it was released on Thursday. Blackburn said she finds it "ironic" that Obama had time to approve the ad, but has yet to explain how four U.S. officials were killed in Bengazi, Libya.

"Did you know before you put your head on the pillow that evening that you had an Ambassador and staff that were in danger?" she asked. "Did you know it was a terrorist attack? When you hob-nobbed in Las Vegas, did you know it was not a video?"

Blackburn also demanded that Obama retract his comments in an interview with Rolling Stone, in which he implied that GOP presidential candidate Mitt Romney is a "bulls*****r."

"Sir, you need to reign (sic) in the inappropriate behavior, retract your Rolling Stone comments and get this First Time ad off the air," she said. "You should be conducting yourself like the American people expect their President to conduct himself."