When Al Franken assumes his new Senate perch Tuesday, the numbers will tell his tale: Minnesota’s second senator, the symbolic 60th vote for Democrats — and No. 100 on the seniority list.

Back of the line is a familiar spot for senators from Minnesota, where voters have sent six new faces to the Senate in the seven elections since 1990. All those freshmen mean the state has missed chances to accumulate seniority in an institution where longevity matters.

Minnesota’s senior senator, Democrat Amy Klobuchar, has 30 months under her belt and is 82nd in seniority.

Only Colorado has a greener duo. Sen. Mark Udall, No. 87, became the state’s senior senator a few weeks into his first term in January when fellow Democrat Ken Salazar resigned to lead the Interior Department. Salazar’s appointed replacement, Democrat Michael Bennet, is 98th.

Senators who stick around are better-positioned to land choice committee assignments, to steer taxpayer dollars to projects back home and to control the agenda. A quarter of the nation’s senators have at least 20 years behind them, with West Virginia’s Robert Byrd marking his 50th anniversary in office this year.

“The more senior a member is, the better chance they have to have their bills move along,” said Glen Krutz, a former senatorial aide who now directs congressional studies at the University of Oklahoma. “When you are there you learn the folkways of the institution, you make contacts, you learn the substance.”

While the 435 seats in the House of Representatives are apportioned based on population — giving behemoths like California, New York and Texas more sway — the Senate is a place where small- and midsized states can gain outsized influence in Washington.

Seniority makes senators from places like Hawaii, Montana and North Dakota prominent players in budget and health care legislation now moving through Congress.

Still, the Senate has moved away from the “whales” and “minnows” power structure — as Texas Sen. Lyndon Johnson, the future president, once described it — in which newer members worked in the shadows while a few gatekeepers determined what got done.

“The Senate is far more democratized and individualized than it was in the earlier point in time,” said Vanderbilt University political scientist Bruce Oppenheimer. “It isn’t powerful committee chairs running the show anymore.”

Oppenheimer, who has written extensively about Senate power, traces the evolution to the late 1950s, when a new crew of liberal Democrats challenged conservative party leaders. Gradually, he said, younger members found it easier to gain spots on coveted committees, like Appropriations, Armed Services, Finance and Foreign Relations.

Seniority is only one measure of Senate clout. Political affiliation is another, and both of Minnesota’s senators have the advantage of being in the current majority.

Franken’s narrow victory over Republican Norm Coleman followed a recount and court fight that lasted eight months. Coleman’s term expired in January, but he held out hope until summer that the count would shift in his favor.