Updated at 3:31 p.m.
Amid a growing vaccination debate, House Speaker John A. Boehner said Tuesday that he thinks all children should be vaccinated.
The Ohio Republican is one of several politicians on both sides of the aisle to comment on the issue as a measles outbreak continues to spread in the United States.
“I don’t know that we need another law, but I do believe that all children ought to be vaccinated," Boehner told reporters.
The speaker's input came hours after likely 2016 presidential candidate Hillary Rodham Clinton waded into the debate, tweeting that "the science is clear" and that "#vaccineswork."
While running for president in 2008, Clinton, responding to a questionnaire, had said that she would support investigating vaccines as a possible cause of autism.
Senate Majority Leader Mitch McConnell (R-Ky.) said he is a "big fan" of vaccinations but didn't say whether they should be mandatory.
House Minority Leader Nancy Pelosi (D-Calif.) said she was "sympathetic to the concerns" of parents who oppose vaccinations out of fear that the drugs could lead to autism. But Pelosi said the scientific studies have made clear there is no connection.
"The fact is, children should be vaccinated," she said at a Brookings Institution forum.
Vaccination has become a contentious issue in the looming presidential race, particularly among presumptive GOP candidates.
New Jersey Gov. Chris Christie had to walk back a statement he made on Monday, when he called for "balance" on the issue of vaccines. Initially, Christie said that "parents need to have some measure of choice" regarding vaccinations. His office later said that the governor "believes vaccines are an important public health protection and with a disease like measles there is no question kids should be vaccinated."
Sen. Rand Paul (R-Ky.), an ophthalmologist, told CNBC that he thinks vaccines should be voluntary. "Many tragic cases of walking, talking, normal children who wound up with profound mental disorders after vaccines.”
Pediatric neurosurgeon Ben Carson, a Republican who also is making gestures toward a run in 2016, said in a statement to the Hill that he strongly supports vaccinations.
"Certain communicable diseases have been largely eradicated by immunization policies in this country and we should not allow those diseases to return by foregoing safe immunization programs, for philosophical, religious or other reasons when we have the means to eradicate them,” Carson said.
Over the weekend, President Obama told NBC News that "there is every reason to get vaccinated — there aren’t reasons to not.”
“I just want people to know the facts and science and the information,” the president said. “And the fact is that a major success of our civilization is our ability to prevent disease that in the past have devastated folks. And measles is preventable.”
Currently, there are more than 100 confirmed cases of measles across 14 U.S. states, according to the Centers for Disease Control and Prevention. Most of those contracting the disease have not been vaccinated.
The resurgence of the disease -- which was eradicated from the United States in 2000 -- has drawn attention to the anti-vaccination movement. The movement defies more conventional political divides; its small but vocal base draws from both conservative and liberal voters who have embraced the largely discredited work of Andrew Wakefield, who wrote in a now-retracted study that he believed the measles vaccine was linked to autism.
Paul Kane and Sean Sullivan contributed to this post