Senate Majority Whip Dick Durbin (D-Ill.) will run for reelection, The Hill has confirmed with two sources familiar with his decision.

Durbin has told high-level Democrats he plans to run for a fourth term in 2014. He's a heavy favorite to win reelection, having won 60 percent of the vote in both of his reelection campaigns.

Illinois Democratic sources tell The Hill that many in the state have expected for weeks that Durbin would run for reelection, since both Illinois Attorney General Lisa Madigan (D) and Illinois Lieutenant Gov. Sheila Simon (D) had been publicly discussing campaigns for office besides the Senate. The two had been viewed by Illinois Democrats as top options to replace Durbin if he decided not to run again, and the senator is close with Simon, whose late father, Sen. Paul Simon (D-Ill.), was a mentor of Durbin's.

Four Democratic senators have decided to retire this year, including Sen. Carl Levin (D-Mich.), who announced his decision on Thursday. The only senator rumored to be looking at retirement who hasn't made a decision yet is Sen. Tim Johnson (D-S.D.), though many expect him not to run again.

The Chicago Tribune first reported Durbin's decision.