ALBANY—She’s a Manhattan liberal who has pushed legalizing recreational marijuana and expanding abortion rights.

He’s an upstate conservative who voted against same-sex marriage and sought to repeal gun restrictions.

On the state Senate floor, Liz Krueger and John DeFrancisco have become the Capitol’s premiere variety show, their colleagues say, engaging in lengthy debates that have inspired some fellow lawmakers and grated on others.

“When Liz and John are going at it, it helps illuminate the issues for a lot of their members, in addition to being entertaining,” said Sen. Mike Gianaris, a Queens Democrat.

Now, at the tail end of a tumultuous legislative session for both Democrats and Republicans, Ms. Krueger and Mr. DeFrancisco have found common ground: stark opposition to Gov. Andrew Cuomo’s economic policies. And rather than fighting each other, the two have begun teaming up to push back against the Democratic governor.

“Nobody ever said democracy was nice and clean and simple, and we both feel strongly it’s worthy of intellectual debate,” said Ms. Krueger, who represents Manhattan’s East Side. “We both have healthy cynicism about New York state’s economic-development models and questions about how much money is going into them.”

Both are long-serving lawmakers who share a commitment to public-policy discussions. Ms. Krueger, 57 years old, is a former food-bank director elected in 2002, taking a seat that had been in Republican control for more than 30 years. Mr. DeFrancisco, 68, is a Syracuse-area attorney and chairman of the Senate finance committee.

“They are both exceptionally smart and substantive, which I think explains why they obviously respect each other despite their frequent disagreements,” said E.J. McMahon, president of the Empire Center for Public Policy, a conservative think tank. “Both are good listeners who make an effort to understand all sides of an issue.”

In a joint interview, the two senators finished each other’s sentences as they rattled off criticisms of Cuomo-led economic initiatives that they have been bringing up on the Senate floor.

Start-Up NY, a tax-relief program for some new businesses in New York that Mr. Cuomo announced two years ago, “is a bad program,” Mr. DeFrancisco said.

“It’s not going to create jobs,” said Ms. Krueger, “and it’s costing a whole lot of tax dollars.”

A tax credit for filming movies in New York is “too generous,” Mr. DeFrancisco said.

“It’s too generous compared to any other state,” Ms. Krueger added.

And a Cuomo plan to grant millions in state funds to three upstate regions that win a contest for the money “is not fair to the rest,” Mr. DeFrancisco said. “And once again the governor picks the winners.”

They both shook their heads.

“One thing John DeFrancisco and I have in common is we actually like to do our homework, look at the facts and say, ‘This one makes sense, and this one really doesn’t,’ ” Ms. Krueger said.

Richard Azzopardi, a spokesman for Mr. Cuomo, said: “Everything they mentioned passed the Senate with bipartisan support and has helped turn around New York’s economy.”

Even when they agree, Mr. DeFrancisco and Ms. Krueger often talk at some length in public, and their debates this year have stretched into the wee hours. Ms. Krueger, a member of the Senate’s Democratic minority, is usually in the position of quizzing Mr. DeFrancisco, a member of the Republican majority.

During an unpredictable session that saw two high-profile corruption arrests of legislative leaders, and subsequent upheaval for both parties, their animated debates have become welcome comic relief for the state’s political circles.

“John DeFrancisco and Liz Krueger are ‘Budget Buddies’—new buddy cop show this fall,” tweeted upstate television reporter Nick Reisman during one of their sparring matches over the state budget last March.

An aide to one upstate mayor called them “the most intriguing pair to come out of Albany since Alexander Hamilton and Elizabeth Schuyler,” referring to the founding father and his wife.

The two are expected to poke fun at themselves at the annual Legislative Correspondents Association show on Tuesday where the Albany press corps roasts state lawmakers and vice versa. Mr. DeFrancisco will deliver the Republican rebuttal. Asked if Ms. Krueger would play a role in his skit, he said “that’s strictly forbidden to talk about, but I’d keep an eye on it.”

But the pair’s debates have also begun to elicit some groans.

“Liz Krueger is smart, but…she asks question after question,” said Sen. Ruben Diaz Sr., a Bronx Democrat. “Sometimes it’s annoying. People get bored, they walk out.”

Asked about the rapport between the two senators, Greg Ball, a former Republican senator for upstate New York who last year moved to Texas and left government, said in an email: “nightmares.”

Even after nuanced debates, the two senators vote down party lines. He voted in favor of this year’s state budget, and she voted against parts of it. He voted against a medical-marijuana program, and she voted for it.

A friendship has developed between the two, nonetheless. During lengthy budget hearings, Ms. Krueger said, they took alternating food breaks while the other monitored the discussions.

And after the Senate was riven by coups in 2009, Ms. Krueger said, they joked they would form a faction called “the Common Sense Party.” An aide to Mr. DeFrancisco said he doesn’t recall that particular comment.

But their differences on major social issues remain stark. Asked if either had converted the other on policy through their friendship, Ms. Krueger joked: “I’m making him more liberal every day.”

Mr. DeFrancisco said: “We’ve both become more reasonable.”

© 2015 Wall Street Journal