One of the Senate’s more liberal members said Friday he intends to take over the powerful Defense Appropriations Subcommittee, at a time when military budgets are contracting.

Sen. Richard J. Durbin, D-Ill., who also serves as the majority whip, said Friday that he is looking forward to running the panel at a critical time in U.S. military history.

“As we wind down the war in Afghanistan, face upcoming budget cuts, and work to prepare our military for future threats, this subcommittee will focus on ensuring our military remains the most powerful, ready and capable force in the world,” he said in a written statement. “We will also work tirelessly to ensure we’re spending wisely, protecting taxpayers and planning well for the future needs.”

While the panel has traditionally been led by defense hawks, Durbin is a strong voice on the left who became a tough critic of the Iraq war and the terrorist detention policies of the George W. Bush administration. He has spent much of his Senate career working to preserve important domestic programs, such as Medicare and Social Security.

His chairmanship comes at a time when lawmakers are wrestling with coming across-the-board cuts, otherwise known as a sequester, that were mandated under the deficit reduction law (PL 112-25) and are now set to go into effect March 1. Any deal to avert sequester would require compromises likely to include defense and domestic discretionary spending cuts, as well as potentially new taxes.

But Durbin has made it clear over the past year that defense will need to accept its share of cuts, saying, for example, that the cuts mandated by the deficit reduction, half of which come from defense discretionary spending, are a “good down payment.”

Durbin will also have to contend with a new continuing resolution that likely would fund defense, along with the rest of government, through the rest of fiscal 2013.

Perhaps understanding the coming challenges, Durbin said, “And as has always been the case, the needs of all our servicemembers — active duty and reserve; in theatre or here at home — will be our first concern.”

Durbin would replace the late senior senator from Hawaii, Daniel K. Inouye, who died suddenly late last year. Inouye was always a strong military booster, and a voice of caution among Democrats, about severe reductions in defense spending. Two other senators — Patrick J. Leahy, D-Vt., and Tom Harkin, D-Iowa, passed up the chance to take Inouye’s spot.

Durbin is closely tied with the Obama administration, having taken the president, then a freshman senator from Illinois, under his wing. Durbin is in frequent contact with Obama, either in person or via phone. Indeed, Obama’s former chief of staff, Pete Rouse, was once Durbin’s chief of staff.

Durbin’s chairmanship could be a boon for Boeing Co., whose corporate headquarters is in Chicago. Boeing, which is currently building the Air Force’s new fleet of aerial refueling tankers, is the country’s second largest defense contractor. Durbin’s rise eases the loss for Boeing of Norm Dicks, D-Wash., the former chairman of the House Appropriations Defense Subcommittee, who retired. Boeing is building its new military tanker program in Washington state.

As chairman of the defense panel, Durbin, who is up for reelection in 2014, will likely see a boost in contributions from the defense industry. In the run-up to his 2008 reelection bid, defense PACs contributed more than $67,000 to his campaign coffers. But that number was dwarfed by far more significant amounts from health care, legal, labor and financial and insurance PACs.

From his new perch on the subcommittee, Durbin likely would improve his already strong chances at reelection. Durbin was reelected in 2008 taking almost 68 percent of the general election vote, the same year of President Barack Obama’s historic victory.

While Durbin is best known for his work in the Financial Services Appropriations Subcommittee, he has been a strong voice on the United States’ terrorist detainee policies, and voted in 2011 to extend the Patriot Act (PL 107-56 ) for four years. In 2010 he voted to ratify the strategic arms reduction treaty with Russian and to allow the repeal of a ban of gays and lesbians serving openly in the military.

Megan Scully contributed to this report.