Coons, a Democrat who holds Biden's old Delaware U.S. Senate seat, said he's optimistic the former vice president will formally announce a 2020 presidential run soon, and expects he will run a "very forward-looking and optimistic campaign."
He said that Biden, "will see the divisions in our country and inspire us to heal them. To work together across them and move us into a better future as a country for all of us."
Amid speculation of a 2020 run, people have raised questions about Biden's past statements and policy positions, including his votes on criminal justice issues.
For example, in the 1980s, Biden supported several bills that increased penalties for drug users, including one that essentially punished the possession of crack cocaine more harshly than powder cocaine -- which critics say disproportionately impacted African Americans.
"There are things that he was involved in, or said, or voted for 25 or 30 or 40 years ago that I expect he will get asked about on the trail," Coons said. "But he has a real and solid record of stepping forward and being a champion for civil rights, for women's rights, for LGBTQ rights."
Coons said he feels "on the whole" the Democratic primary electorate will be satisfied with Biden's record.
"Joe Biden has a record that allows him to say that making big and bold progressive promises on the campaign trail is one thing, having a real record of actually delivering on those things is quite another," Coons said. "Real leadership is actually enacting legislation that advances access to health care, that reigns in Wall Street."
Coons has guaranteed that Biden is nearing a decision to run for president and the former vice president has been dropping hints in the past few weeks.
"I'm told I get criticized by the new left," Biden said during a speech Saturday at a fundraising dinner, in reference to claims he would be a more moderate candidate compared to some of the current presidential contenders. "I have the most progressive record for anybody running for the United--"
While cheers erupted around him, Biden quickly clarified his comment, chuckling while he looked down at the podium and crossed himself.
"I didn't mean it," he said. "Of anybody who would run."
While Biden has some of the most support of the current 2020 hopefuls with a Monmouth University poll released Monday finding that 28 percent of Democrat or Democratic leaning voters surveyed would support Biden for the party's nomination, a Wall Street Journal/NBC News poll earlier this month hinted that his age may make him less appealing to some voters.
The Wall Street Journal/NBC News poll found that 62 percent of Americans surveyed said that a candidate over the age of 75 gave them some reservations or made them very uncomfortable. Biden is 76 years old.
Coons said Sunday that Biden's long political career will be an asset that will "inspire a new and younger generation of political activists."
"Because Joe Biden's life history, his whole story, is about getting up when life has knocked him down, about connecting with working families of all backgrounds across America and of being a champion for civil rights, civil liberties, inclusion and justice in his decades in public leadership," Coons said.