By Fernando Alfonso III, CNN

(CNN) -- Sen. Elizabeth Warren paid tribute to the Black Lives Matter movement in a subtle but pointed way during her speech Wednesday night at the Democratic National Convention.

As the Massachusetts Democrat addressed the convention from the Early Childhood Education Center in Springfield, Massachusetts, the letters "BLM" could be seen on a shelf over her left shoulder.

"We all need to be in the fight to get Joe and Kamala elected. And after November, we all need to stay in the fight to get big things done," Warren said in her remarks. "We stay in the fight so that when our children and our grandchildren ask what we did during this dark chapter in our nation's history. We will be able to look them squarely in the eye and say, we organized, we persisted, we changed America."

Warren has fought to pass legislation against racial injustice in the US on Capitol Hill.

In June, Warren introduced an amendment calling on the Department of Defense to rename military bases named after Confederate soldiers. The amendment came after the police killing of George Floyd in Minneapolis in late May.

The amendment specifically called for the removal of names of Confederate leaders from all military assets -- whether a base, installation, facility, aircraft, ship, plane or type of equipment -- within three years.

The plan was adopted behind closed doors by voice vote with the support of some Republicans, even as President Donald Trump condemned any action to remove Confederate leaders' names from military bases, and the White House vowed to veto any such legislative effort.

And speaking on her amendment from the Senate floor on June 30, Warren declared that Black lives matter.

"For weeks, all across this nation, Americans have taken to the streets to call for justice and call for an end to the racist violence that has stolen far too many Black lives," she said at the time. "We say the names of George Floyd and Breonna Taylor and Ahmaud Arbery and Atatiana Jefferson and so many other Black men and women to reaffirm the simple but powerful truth that they mattered. Their lives mattered. Black lives matter."

"BLM" was not the only hidden message Warren included in the background of her speech Wednesday night. Other references included a US Mail shirt to promote the message of protecting the US Postal Service and letters spelling out DBFH to represent the senator's "Dream Big, Fight Hard" message.