Hillary Clinton's first national TV ad goes after Republicans for their "partisan" investigation into the attack on our diplomatic compound in Benghazi.  The ad uses a bonehead statement by Rep. Kevin McCarthy, who is running for speaker of the House, hinting that one of the reasons for Hillary's falling poll nunbers is what the Benghazi Committee has exposed.

The Hill:

A new ad released by the campaign on Monday evening features a clip of House Majority Leader Kevin McCarthy (R-Calif.) giving the special House panel credit for damaging Clinton's poll numbers.

The 30-second spot is the first one the campaign is running nationally on cable television, underscoring the political gold mine that Clinton's team senses in McCarthy’s comments. 

“The Republicans finally admit it,” a male narrator says in the video before a clip of McCarthy’s comments.

“Republicans have spent millions to attack Hillary because she’s fighting for everything they oppose.”

The ad on Monday came after Clinton went on the offensive over Republicans' investigation of the Benghazi attack.

In a nationally televised town hall earlier in the day, Clinton accused Republicans of exploiting the four Americans killed in Libya in 2012 merely to knock down her presidential campaign.

“Look at the situation they chose to exploit, to go after me for political reasons, the death of four Americans in Benghazi,” she said.

The ad also comes just more than two weeks ahead of Clinton’s appearance in a public hearing of the Benghazi panel.

In turning the tables on House Republicans, Clinton is seeking to get out from under questions about her use of a private email server while secretary of State — which the Benghazi committee helped to reveal — and instead set the tone for her Oct. 22 appearance before the committee.

McCarthy’s comments were seen as damaging for the California Republican, who is the favorite to become the next House Speaker.

McCarthy is still likely to win the vote for speaker late this month, but serious questions have been raised about his judgment.  His statement damaged the credibility of the committee at a critical moment when Clinton's emails on Benghazi as well as her upcoming appearance before the Committee were bringing the investigation to a head.

It was a gift that Clinton desperately needed.  Now her appearance will likely be more about the partisan nature of the proceedings rather than what Clinton did both before and after the attack on our consulate.  And it will make it difficult to get to the bottom of the incident that cost four Americans their lives, including our ambassador.