Rep. Elijah E. Cummings (D-Md.) speaks to members of the media. (Andrew Harnik/Associated Press)

Rep. Elijah E. Cummings (D-Md.) endorsed Hillary Clinton on Sunday, after months of staying neutral in the presidential contest because of his post as the ranking Democrat on the House Committee on Oversight and Government Reform.

“Families in Baltimore who are hurting right now need more than the promise of a political revolution,” Cummings wrote in an op-ed submitted to The Washington Post.

He added that Clinton “not only understands the challenges facing Baltimore and other cities, she’s laid out a clear and detailed agenda that meets those challenges head-on.”

A Washington Post-University of Maryland poll released last week showed Clinton with a clear lead over Sen. Bernie Sanders (Vt.) in Maryland’s Democratic primary, but her advantage has narrowed over the past few months. She leads Sanders 55 percent to 40 percent among likely Democratic voters in the state; a Baltimore Sun poll last month showed her pulling ahead by roughly 30 percentage points.

With Cummings’s endorsement, every Democratic member of Maryland’s congressional delegation has backed Clinton before the April 26 primary.

On the Oversight Committee, Cummings was Clinton’s chief defender against Republicans during their probe into the September 2012 attack in Benghazi, Libya. The investigation, he said in the fall after her testimony, was an “abusive effort” to “derail Secretary Clinton’s presidential campaign.” But he held off from endorsing her at the time.

The investigation is ongoing. Cummings said in a statement last week that the effort had “shockingly become even more partisan, secretive, and dysfunctional.”

Clinton is in Maryland on Sunday for an organizing event in Baltimore with retiring Sen. Barbara A. Mikulski (D).