WASHINGTON ? US President Barack Obama paid tribute on Wednesday to fellow political trailblazer Edward Brooke, who in 1966 became the first African-American elected to the Senate by popular vote.

In the US Capitol rotunda, Obama presented Brooke, 90, with the Congressional gold medal, the highest civilian award given by the government's legislative branch.

"Today's honor bears a unique significance: bestowed by this body of which he was an esteemed member; presented in this place where he moved the arc of history; surrounded by so many ? myself included ? who have followed the trail that he blazed," said Obama as he stood next to the former senator from Massachusetts.

Brooke, who served as a Republican from 1967 to 1979, was the first of just three blacks popularly elected to the Senate in the modern era, including Carol Mosely Braun (1993 to 1999) and Obama himself (2005-2008).

Other African-Americans had previously served in the Senate before Brooke, but they were chosen by state legislatures.

Obama, a Democrat, hailed Brooke as someone who managed to navigate a fiercely segregated America and "spent his life breaking barriers and bridging divides."

The only black senator currently serving in the upper chamber is Roland Burris, who was appointed senator from Illinois to replace Obama after he won the White House in 2008.