This year may mark the end of an era in Maine politics. It could be that the long shadow of Sen. Margaret Chase Smith begins to fade away.

The two most prominent and admiring of her successors are fighting this year to hang on to political office. The chance that either of them will emerge triumphant on Election Day seems to me ever smaller.

Back in 1948, not long after Smith defeated a sitting governor to win the Republican nomination for U.S. Senate, she “joined two of her closest friends on the porch of their home” in Farmington, “holding their 6-month-old baby in her lap while sharing her triumph over the establishment wing of the state’s ruling party and the shattering of a very high glass ceiling,” as Colin Woodard wrote for the Press Herald 70 years later.

Smith later wrote a letter to that baby, telling her she had “much to live up to because your two brothers will expect a great deal of you but I know that you can do it.”

The baby was Janet Trafton Mills. Janet Mills went on to become a friend of Smith’s, who served in the U.S. Senate until she lost the 1972 race, and ultimately took the oath of office as Maine’s first female governor.

The winter before that race, 18-year-old Sue Collins of Caribou boarded a plane for her first-ever flight, bound for the U.S. Senate. She was one of two students selected for the honor.

Telling me about it years later, Sen. Collins said Smith talked with her for a couple of hours about everything from the armed forces to the definition of full employment. The message that came through loudest and clearest, she recalled then, was the importance of “standing tall for what you believe in.” Collins left thinking “that women can do anything.”

Collins described “that pivotal meeting” as “the beginning of my journey to the Senate.”

“I am so proud to hold the seat of a senator whose entire public career personified integrity and service,” she said later.

For Mills, too, Smith left a lasting impression.

When Mills took the oath office as the first woman attorney general in Maine, she said Smith “was always a role model for me growing up. She was a woman of both grit and integrity who held high public office with grace and vision.”

She also “held her ground and didn’t take grief from anyone,” Mills added, “even from presidents and foreign leaders.”

It’s quite something that two of the most influential Mainers in the past half century each point to the groundbreaking Smith as one of the reasons they chose a career in politics — and pursued it successfully. One of them became a five-term U.S. senator, the other a prosecutor, attorney general and governor.

Time marches on. Smith died at the age of 97 more than a quarter century ago. Collins is now 73. Mills is 78.

Smith herself showed us that campaigns can be just as rough on old politicians as they often are on young ones. She lost a reelection bid when Maine voters wondered if she’d grown too weary and too distant from the state that had hoisted her to international fame.

Mills may not survive a primary against a hard-charging Graham Platner, unknown a year ago and soaring in poll after poll while attracting huge crowds eager for someone new.

Collins is set to move on to the general election in November. Although tens of millions of dollars will pour into Maine to try to influence the outcome of her race, it isn’t clear she can win again.

If neither candidate prevails, this election year may amount to Margaret Chase Smith’s last hurrah — until somebody else chooses to pick up the torch.