House Republican leaders said this week that they are determined to pass reforms to federal mental health laws, potentially delivering a jolt to legislation that has been mired in partisan disputes for nearly three years.

House Speaker Paul D. Ryan (R-Wis.) endorsed a long-simmering mental health overhaul at a Tuesday morning news conference immediately after offering his condolences to the victims of Friday’s shootings at a Planned Parenthood clinic in Colorado.

“Clearly we can do more, and one common denominator in these tragedies is mental illness, and that is why we need to look at fixing our nation’s mental illness health system,” Ryan said, pointing to a reform bill authored by Rep. Tim Murphy (R-Pa.) now awaiting final action in the Energy and Commerce Committee. “I’m sure that members of both parties have lots of ideas in this area, but we should make this a priority to prevent the violence and to protect our citizens.”

Separately, House Majority Leader Kevin McCarthy (R-Calif.) also pointed to Murphy’s bill Monday in response to a question about the Colorado shootings: “I think you’ll see a number of members working trying to move that bill forward from Energy and Commerce to dealing with this issue.”

Congressional Republicans have frequently pointed to mental health in their responses to mass shootings, but Ryan and McCarthy’s remarks this week were notable in their endorsement of a specific piece of legislation — one that had seemed to be gaining bipartisan support earlier this year.

“The common theme with these kinds of shootings is mental illness, and this is something that we should not be ignoring,” Ryan said. “Congressman Murphy has a very comprehensive effort underway. He’s put years into this, and that is why we want to see this process all the way through, and this is something that requires our attention.”

Murphy’s bill would create a new assistant secretary of Health and Human Services to oversee substance abuse and mental health, overhauling the oft-maligned Substance Abuse and Mental Health Services Administration. It would also put a new emphasis on evidence-based treatments, and encourage court-ordered “assisted outpatient treatment” programs for those who are mentally ill but who are not eligible for involuntary commitment.

A parallel effort is underway in the Senate, led by Sens. Bill Cassidy (R-La.) and Chris Murphy (D-Conn.), who has led efforts to pass a mental health bill since the 2012 killings at Sandy Hook Elementary School in his home state,

House and Senate aides said this week that mental health legislation is unlikely to win floor consideration before year’s end, with Congress already scheduled to finalize major transportation and education bills, extend major tax provisions and pass legislation to fund the government through September. But Ryan’s endorsement could help push mental health reform to the front burner in the new year.

But pitfalls remain — none more significant than the third-rail issue of gun control.

A separate Senate bill more focused on the criminal justice aspects of mental health than the clinical aspects, authored by Majority Whip John Cornyn (R-Tex.), also has significant support among Republicans, and GOP aides say it could become incorporated into any package of mental health reforms. A companion House bill was recently introduced by Rep. Martha McSally (R-Ariz.).

But those bills includes provisions dealing with the ability of those adjudicated as mentally ill to restore their rights to buy and carry weapons, which has given the bill the crucial blessing of the National Rifle Association — and has gun-control advocates and Democrats deeply wary.

Democratic leaders suggested Tuesday that they would not give Republicans a free pass to move forward with a mental health bill and then claim they had mounted a serious response to mass shootings in America.

“Of course I’m happy to work on anything dealing with mental health,” Senate Minority Leader Harry M. Reid (D-Nev.) said Tuesday. “But it seems to me that anytime — and that’s often now — that we have one of these horrible murders take place, the Republicans go, ‘We should do something about mental health.’ ”

Said Minority Whip Richard J. Durbin (D-Ill.), “The Republicans address every gun violence tragedy as another opportunity to discuss mental health without discussing guns, and that to me is very shortsighted. … There’s a much larger issue about the access to guns, too.”