With the Supreme Court set to hear arguments on same-sex marriage next week, two more prominent lawmakers took time to express their unwavering views on the issue.

When asked about his defense of the Defense of Marriage Act given public opinion has shifted to support marriage equality, House Speaker John Boehner said that while his personal belief is that marriage should strictly be between a man and woman, it should be up to the justices to decide whether the act should be upheld as constitutional.

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"In our system of government, the administration doesn't get to decide what's constitutional. The Supreme Court does," Boehner, R-Ohio, said. "Our financing the lawsuit was to make sure that the proper forum was used to make sure that we know what's constitutional and what isn't."

In a recent Washington Post-ABC News poll, results indicate that the shift in public support for gay marriage is at an all-time high, with 58 percent of Americans now supporting marriage equality. Just 36 percent of those polled believe same-sex marriage should be illegal.

INFOGRAPHIC: Support for Gay Marriage

The Supreme Court will hear arguments against the Defense of Marriage Act as well as California's Proposition 8 when it convenes next week.

House Minority Leader Nancy Pelosi said in a Capitol news conference today that gay marriage was an issue "near and dear" to her heart and that she predicted the law would be ruled unconstitutional.

READ MORE: Politicians Shift on Gay Rights

Asked about a bill that is moving through the Democratic-controlled New Jersey state legislature that aims to ban gay conversion therapy, a controversial practice in some states where homosexual minors are counseled to believe they are straight, Pelosi discounted the effectiveness of the treatment.

"I believe in science, and I believe in evidence, and I don't think there's any scientific evidence that says that we should have such a public policy that tries to do what you describe," Pelosi, D-Calif., said. "But I do know it's disrespectful and discriminatory, and therefore I would oppose the conversion therapy and support the bill, as we have in California." Though a bill to ban gay conversion therapy was passed in California late last year, it has currently been placed on hold by a federal appeals court and awaits further action.

In contrast to Boehner, fellow Ohioan Republican Sen. Rob Portman became the second-sitting GOP senator to endorse gay marriage, in an op-ed last week.

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While the topic has taken new life on Capitol Hill in the wake of Portman's reversal, former Secretary of State Hillary Clinton, a potential presidential candidate in 2016, also came out in support of gay marriage in an ad for the Human Rights Campaign earlier this week.