Daniel Squadron, the lean 28-year-old candidate for the state Senate introducing himself to voters outside a Brooklyn subway stop on a recent morning, had not been born when the incumbent he is trying to oust, Martin Connor, was first elected.

But in this hard-fought race, age and experience don’t seem to be stalling Mr. Squadron, a low-talking, bearded graduate of Yale University who is mounting a fierce campaign against his opponent and running on the line that he is best equipped to fix the culture of governance in Albany.

On the street, talking to voters, he had the ease of a practiced politician, greeting New Yorkers with steady persistence just before they descend the steps of a Bergen Street subway station. When one man heading down the steps said he was not from the district, Mr. Squadron responded without missing a beat: “Welcome. It’s a beautiful area.”

This is how Mr. Squadron has been spending his mornings in the run-up to Tuesday’s primary. Taking a page from his political mentor and former boss, Senator Schumer, he says he has knocked on more than 6,000 doors in the district, which stretches from Lower Manhattan into Brooklyn, and includes Brooklyn Heights, Carroll Gardens, and Cobble Hill.

“To have someone there at the door or at the subway talking about these issues is exciting,” he said. “Sometimes people say, I didn’t know folks did this anymore.”

He has racked up a string of high-profile endorsements from Mr. Schumer, Mayor Bloomberg, and Rep. Anthony Weiner, as well as the New York Times and local newspapers in the district.

But the support isn’t swaying every voter, including even some who say they are disenchanted with Mr. Connor.

“Connor has clearly been a disappointment, but the question is whether Squadron is ready and sufficiently independent,” a district resident and an education professor at Brooklyn College, David Bloomfield, said recently.

Mr. Squadron grew up in Riverdale and attended the Fieldston School. His father, Howard Squadron, who died in 2001, was a lawyer who was once chairman of the Conference of Presidents of Major American Jewish Organizations as well as president of the American Jewish Congress.

Before running for office, Mr. Squadron worked as a communications director on the Transportation Bond Act campaign and spent time working for the city’s Department of Education.

Mr. Squadron says that in addition to trying to shake up Albany, his top priorities are to focus on neighborhood preservation, local development that is driven by residents, preserving “affordable” housing, and improving the city’s public schools.

He says that if Democrats win a majority of seats in the Senate, it will be a historic moment and “an opportunity to build something different.”

The incumbent, Mr. Connor, says that his seniority makes him better equipped to capitalize on a Democratic-controlled Senate if it flips this fall.

“I have the experience and the record to make the most of that majority. To make sure the reforms that we promise to bring about happen,” Mr. Connor said this week during a debate organized by Citizens Union. “I will be in a position to make sure we keep that commitment.”