Staffers close to former Secretary of State Hillary Clinton lobbied senior House Democrats to appoint Democratic lawmakers to the House Select Committee on Benghazi to serve as a first line of defense against GOP criticisms of her behavior, Politico reported Thursday.

The back-channel moves are the strongest indicators yet that Clinton is planning a presidential run in 2016. Clinton stands to benefit from litigating the Benghazi issue before the presidential contest, preventing the emergence of damaging facts or testimony during the campaign, relegating the events in Libya to "old news."

On May 21, House Minority Leader Nancy Pelosi, D-Calif., named five Democrats to the panel, after initially planning to boycott the probe.

Meanwhile, Democrats continue to accuse Republicans of scandal-mongering.

“Republicans are making it clear they plan to use the power of the Benghazi Select Committee to continue to politicize the tragedy that occurred in Benghazi, which is exactly why Democratic participation in the committee is vital,” one unnamed source close to the Clintons told Politico.