U.S. Sen. Tom Harkin (D-Iowa) is set to take over the chairmanship of the Senate’s powerful Health, Education, Labor, and Pensions (HELP) Committee, the Washington Post reports. The position was held by former Sen. Ted Kennedy until his death last month.

Harkin, who currently chairs the Agriculture Committee, is second in seniority behind U.S. Sen. Chris Dodd (D-Connecticut) on the HELP Committee, but Dodd has reportedly decided hold on to his chairmanship of the Banking Committee rather than taking over Kennedy’s old seat.

As its name implies, the HELP Committee’s jurisdiction spans a wide swath of domestic policy, including health care reform. Dodd’s decision elevates Harkin to a position of considerable power in both symbolic and practical terms.

An outspoken, politically secure liberal who will not face re-election until 2014, Harkin’s most significant legislative achievement is the Americans with Disabilities Act, which he spearheaded in 1990 at the end of his first Senate term. In 1992, he unsuccessfully ran for the Democratic presidential nomination. He is the longest-serving Democratic senator in Iowa history.

Harkin’s move would likely make U.S. Sen. Blanche Lincoln (D-Arkansas) chair of the Agriculture Committee, according to the Post.