ATLANTA (CNN) - Georgia Rep. John Lewis, who backed Hillary Clinton in his state's Democratic presidential primary, announced Wednesday that he is switching his support to Barack Obama to reflect the will of his constituents.
"Something is happening in America," the 11-term congressman, a bloodied veteran of the civil rights movement, said in a statement issued by his office.
"There is a movement, there is a spirit, there is an enthusiasm in the hearts and minds of the American people that I have not seen in a long time, since the candidacy of Robert Kennedy."
In a statement issued Wednesday afternoon, Obama called Lewis "an American hero."
"I am deeply honored to have his support," he added.
Lewis endorsed Clinton, the senator from New York and former first lady, in October. But his central Atlanta district went strongly for Obama, the senator from Illinois, in Georgia's Feb. 5 primary - forcing what he called "a difficult decision" for him.
"As a U.S. representative, it is my role not to try to subdue or suppress the will of the people, but to help it prosper and grow," he said.
Lewis is a member of the Democratic leadership in the House of Representatives and a Democratic "superdelegate," one of the elected officials and party leaders who will not be bound by the results of primary elections or caucuses when they vote on the party's presidential nominee at its August convention in Denver. He is also a longtime friend of Clinton and her husband, former President Bill Clinton, and said he had "a deep and abiding love" for both.
But he added, "I think the candidacy of Sen. Obama represents the beginning of a new movement in American political history that began in the hearts and minds of the people of this nation. And I want to be on the side of the people, on the side of the spirit of history."
Lewis' announcement comes less than a week before next Tuesday's Democratic primaries in Texas and Ohio, which Clinton is banking on to break the Illinois senator's 11-contest winning streak in the Democratic race. The two held a heated debate in Cleveland on Tuesday.
Clinton did not answer reporters' questions about Lewis' reversal at a Wednesday afternoon campaign stop in Zanesville, Ohio. But campaign spokesman Doug Hattaway told CNN that the candidate "respects Congressman Lewis enormously, and she respects his decision."
Lewis declined further comment to reporters as he left the House floor Wednesday, telling them, "I'll let the statement speak for itself."
In announcing his endorsement of Clinton in October, Lewis called her the Democratic candidate "best-prepared to lead this country at a time when we are in desperate need of strong leadership." But despite the support of Lewis and other leading African-American politicians, Obama beat Clinton by better than 2-to-1 in Georgia's primary, with overwhelming support from black voters.
Lewis' fellow Georgian, Rep. David Scott, has told news outlets he would support Obama in Denver rather than go against the will of voters in his suburban Atlanta district.
The Lewis endorsement follows Tuesday's endorsement of the Illinois senator by former Democratic presidential candidate Chris Dodd, who called for the party to unite "behind a candidacy that expresses the aspirations, the hopes, the ambitions of millions and millions of Americans."
Dodd warned that Democrats are in danger of damaging their fortunes in November with a divisive campaign, but said he is not suggesting Clinton should drop out of the race. The Connecticut senator dropped his presidential bid after the Iowa caucuses Jan. 3.
Obama currently leads Clinton in the number of convention delegates won in the Democratic contests to date, 1,184 to 1,031, according to the latest CNN estimates. Clinton has the support of more superdelegates, however, leading Obama 237-181, according to CNN's count.
– CNN's Sasha Johnson, Candy Crowley, and Alex Mooney contributed to this report