Senate Democrats appear increasingly serious about changing the chamber’s filibuster rules, and they have called in a veteran of the fight who will share tips from his own playbook — Walter Mondale.

The former vice president, who will appear at a Rules and Administration Committee hearing today, steered a rules change in 1975 while he was a Democratic Senator from Minnesota that lowered the number of votes needed to break a filibuster from 67 to 60.

“I hope reforms will be ready for adoption at the outset of the new Congress, next January,” Mondale will tell the committee, according to prepared remarks.

Freshman and sophomore Democrats have been forcefully pushing leadership to revisit the topic, making the case that Republicans have led an unprecedented number of filibusters and held up scores of noncontroversial nominees.

“The first issue is building the support to get that vote,” said Sen. Tom Udall (D-N.M.), who noted that he’s “talking with everybody” about his legislation to revamp the filibuster rules.

The appetite for upending Senate rules, however, is difficult to gauge. Conference Vice Chairman Charles Schumer (N.Y.), who also chairs the Rules and Administration Committee, raised the issue to colleagues Tuesday during the Democrats’ weekly caucus luncheon, but in an interview he was careful to describe the hearing simply as “informative, education, exploratory.”

“The mandate I think my caucus has given me” and Majority Leader Harry Reid (D-Nev.) has given, “is to look if there is any way you can change the rules and how,” Schumer said.

Senate Republicans say that filibusters give Members influence in the legislative process — and further counter that Democrats have abused the procedural tool in the past. Republicans also predict that the Democratic majority will be thinned so significantly in November that party leaders next year won’t have the votes to implement drastic change in Senate rules.

Sen. Ben Nelson, a member of the bipartisan Gang of 14 that negotiated a set of guidelines to consider judicial nominees and avoid constant filibusters in 2005, said he was shaky on taking up filibuster reform next year.

“I’m anxious to see what they have to say,” the Nebraska Democrat said of the hearing. “But without knowing specific things, I don’t know if I’m inclined to see the need for any reform.”

Sen. Mary Landrieu, also a member of the Gang of 14, said, “It’s a very delicate balance and I haven’t made a final decision.”

“I don’t believe in getting rid of the filibuster; I believe in getting rid of the abuses of the filibuster that have been very obvious,” the Louisiana Democrat added.

Rather than lowering the threshold for reaching cloture — the key to broadly reforming the filibuster — Landrieu hinted that Democrats would consider tweaking rules on secret holds and stalling tactics on motions to proceeds to legislation. Sens. Ron Wyden (D-Ore.), Chuck Grassley (R-Iowa) and Claire McCaskill (D-Mo.) have all made recent efforts to rein in secret holds, and aides said Tuesday those efforts could see floor action next year.

Still, aides note today’s exercise in the Rules Committee is one that freshmen and sophomore Members have pushed for and one that Schumer — who led the Democratic Senatorial Campaign Committee, which brought in the fresh faces, during the previous two cycles — has been eager to champion.

“We’re going to educate everybody on the bottom line,” Udall said. “We clearly have support right now for reform of the secret holds.”