U.S. Rep. John Lewis endorsed former Vice President Joe Biden’s bid for the White House on Tuesday, saying he’d use his pulpit as a veteran leader of the civil rights movement to “help elect a man of conscience” in November.

The Georgia Democrat said he would help Biden burnish his appeal with older African-American voters, some of his party’s most reliable supporters, at a time when the coronavirus crisis has thrown traditional campaigning into disarray.

“He’s a man of courage. A man of great conscience. A man of faith. He will be a great president,” said Lewis. “He will lead our country to a better place. He’ll inspire another generation to stand up, to speak up and speak out. To be brave and to be bold.”

Lewis also expressed sharp concerns that the pandemic could lead to lower election participation and breed more confusion at a difficult moment.

“I’m worried whether we’re going to be able to have a free and clean election. I just hope that in spite of whatever is going on now, that people will not be afraid to come out and vote. We have to vote. We fail to vote, we don’t count,” said Lewis.

“I’ll do everything in my power, whether in Georgia or some other parts of the country, to encourage people to vote,” he added. “We cannot find an excuse not to vote. We must make it easy and simple and convenient for everyone to participate in the democratic process.”

The congressman joins a growing chorus of supporters of Biden in Georgia ahead of a May 19 primary against Vermont Sen. Bernie Sanders that’s already been postponed once and could be pushed back to June as a growing pandemic keeps millions of residents at home.

Biden has amassed far more endorsements than any other White House hopeful in Georgia, a collection of supporters that includes Atlanta Mayor Keisha Lance BottomsU.S. Rep. Sanford Bishop, former Justice Department chief Sally Yates and dozens of influential state legislators.

But his blowout victory in South Carolina’s primary, followed by a series of coast-to-coast wins, served as a magnet to attract a wave of new supporters. Many expressed outspoken concerns that Sanders, who has so far stayed in the race, could bring lasting damage to down-ballot candidates.

In the most recent Atlanta Journal-Constitution poll, Biden led Sanders by more than 40 percentage points. But the timing of the presidential primary is still in doubt. The state's March vote was pushed to May because of the pandemic, and a growing number of officials seek another delay.

Lewis, who is suffering from late-stage pancreatic cancer, offers Biden the support of one of the nation’s most well-known African-American figures – and a veteran lawmakers who has played pivotal roles in past campaigns.

His flip from Hillary Clinton to Barack Obama in 2008 gave the upstart Illinois senator instant credibility and was one of several major developments in that turbulent race. Eight years later, he was among Clinton’s most forceful advocates to help her shore up black support as she faced Sanders.

In a conference call, Lewis didn’t invoke the names of either Sanders or President Donald Trump. But he said he plans to travel the nation to stump for the former vice president, adding that “we need Joe Biden more now than ever before.”

Asked his advice for Biden’s running-mate, Lewis expressed enthusiasm at the prospect he could select a woman of color but offered no hints about who his preference should be.

Biden has vowed to pick a woman to join him on the ticket, and three Georgians are among the potential contenders: Former gubernatorial candidate Stacey Abrams, Atlanta Mayor Keisha Lance Bottoms and Yates.

“It’ll be good to have a woman who looks like the rest of America: Smart. Gifted. A fighter. A warrior. And we have plenty of able women,” Lewis said, adding: “I think the time has long passed to make the White House look like the whole of America.”

Watch: Lewis recorded a video highlighting his endorsement: