CAPE ELIZABETH — One of the principal members of Maine’s political pantheon is Margaret Chase Smith, a Republican who served in the U.S. Senate from 1949 through 1973 and was the first woman to serve in both houses of Congress.

She is perhaps best known for her 1950 speech “Declaration of Conscience,” criticizing McCarthyism, and her early denunciation of anti-communist demagoguery seems uncannily relevant in today’s fraught political world. But even close observers of politics know little of the full substance of Smith’s landmark speech. When I tracked it down and read it, I was surprised to find a hidden strand that is also especially relevant given today’s poisoned political ecosystem.

Most people know “Declaration of Conscience” for its denunciation of the tactics of Wisconsin Republican Sen. Joseph McCarthy. Smith criticized the “irresponsible words of bitterness and selfish political opportunism” in what she otherwise considered legitimate concerns over communist influence in America.

“The American people are sick and tired of being afraid to speak their minds lest they be politically smeared as ‘communists’ or ‘fascists’ by their opponents,” she said. “I am not proud of the way in which the Senate has been made a publicity platform for irresponsible sensationalism. I am not proud of the reckless abandon in which unproved charges have been hurled from this side of the aisle.”

What is perhaps less well-known about the speech is its charged partisan content. Smith minced no words in her criticism of the administration of President Harry S. Truman. “The Democratic administration has completely confused the American people by its daily contradictory grave warnings and optimistic assurances – that show the people that our Democratic administration has no idea of where it is going,” she said.

She saw both the opportunity and the need for a Republican victory in the next presidential election. “Surely it is clear that this nation will continue to suffer as long as it is governed by the present ineffective Democratic administration,” she said.

But Smith didn’t advocate victory at all costs. “Yet to displace (the Truman administration) with a Republican regime embracing a philosophy that lacks political integrity or intellectual honesty would prove equally disastrous to this nation,” she said. “Surely we Republicans aren’t that desperate for victory.”

Today, the Republican Party obviously has no problem winning elections. On the federal level, Republicans hold the executive branch and control both houses of the legislative branch. They even have an edge in the judicial branch. The challenge of the party today is not winning power but wielding it effectively. And it is here that the spirit of Smith’s partisan words seems especially relevant.

If Smith were alive today, she might well be criticizing demagoguery not because it diminishes her party’s electoral prospects, but because it gets in the way of the party’s governing responsibly. We need only look at the bombast, chicanery and confusion that characterized the recent effort to roll back the Affordable Care Act. The Republican Party rode to victory last November in part on anger over Obamacare, yet lacked a cohesive plan for replacing it. In the end, the rhetoric that energized voters did not translate into policy or even legislative strategy, and the effort collapsed.

I myself am in no position to give advice to the national Republican Party. I am a lifelong Democrat, and I was named after a Democratic president. But I believe it is in the interest of all Democrats to have a well-functioning Republican Party, one that produces responsible leaders.

Despite my Democratic roots, I always had the sense that the Republican Party put forth informed, experienced, well-vetted candidates. I may have vehemently opposed Ronald Reagan and George W. Bush, yet I acknowledge that both had been elected governor – twice each – of large states. They were seasoned and accomplished by the time they reached the Oval Office. Today, responsibility is in short supply, and Washington lurches from drama to drama.

As Margaret Chase Smith said in her signature speech, about the role of her Republican Party: “We do have the responsibility of rendering constructive criticism, of clarifying issues, of allaying fears by acting as responsible citizens.” Today, the leaders of the Republican Party – all parties, really – should rededicate themselves to the notion of governing responsibly, starting with the process of encouraging, developing and supporting responsible candidates and leaders.