For the more than one week since a Republican takeover of the State Senate plunged the Capitol into chaos in Albany, probably no other senator has endured more political pressure than Democrat William T. Stachowski of Lake View.

Stachowski has been lobbied, cajoled, offered various political plums, singled out and generally thrown into the statewide spotlight as the senator most likely to join what was, from the start, a fragile GOP coalition that Monday turned into 31-31 gridlock.

But it’s not going to happen.

“I’ve always felt strongly that if you’re elected as a Democrat, you should be a Democrat,” Stachowski said Monday. “And I don’t really see this as a coalition government, and I’m not sure it’s good government.”

Speaking for the first time in any detail on the situation, Stachowski said coup instigator B. Thomas Golisano and his political point man, G. Steven Pigeon, have both personally urged him to join the movement that has roiled the Legislature’s upper house.

But despite both men predicting that many more Democrats would follow Sens. Pedro Espada of the Bronx and Hiram Monserrate of Queens into the GOP fold, Stachowski has yet to see even a hint of such movement. In fact, Monserrate returned to the Democratic caucus Monday.

While ethical questions have been dogging Espada and Monserrate, Stachowski is seen as a potential prize catch who would add instant credibility to the Golisano-Pigeon effort.

But Stachowski said it won’t happen.

“I said [to Golisano] that I would give this consideration if I saw this as a true coalition government, and that I would get back to him,” Stachowski said. “I’ve been watching, and so far I haven’t seen it.”

While Golisano, Pigeon and others have referred to the coup’s impact as a coalition government, Stachowski says he sees only 30 Republicans plus what Monday became only one Democratic defector. “I think integrity plays a role in being an elected official, and it’s very important to me,” Stachowski said. “And I hope the people in my district appreciate it.”

Stachowski, 60, has enjoyed a relatively tranquil life throughout more than three decades in elected office. The son of legendary East Side Democratic leader Stanley J. Stachowski, who died in 1997, he grew up in Democratic politics and has proved a low-key legislator who shuns the spotlight.

As a result, he faced only token opposition in the heavily Democratic district throughout his 28-year career. But after the Republican candidate, former Buffalo police Detective Dennis A. Delano, gave him a genuine scare in the 2008 election, Stachowski has come under more scrutiny by people who see him as vulnerable to challenges from both inside and outside the Democratic Party.

But he said Monday that he has no interest in joining any so-called coalition that offers no guarantees of meaningful reform. He also said he views GOP outreach efforts as disingenuous after Republicans such as Sen. George D. Maziarz of Newfane have gone out of their way to criticize him.

“They just spend a year and a half beating the hell out of me, and now they’re welcoming me with open arms?” Stachowski said.

Stachowski did not dispute that suggestions about becoming Finance Committee chairman have been made to him, with a public spin that he would be able to achieve more for upstate in that post. But he said the GOP did little for upstate over the 40 years that it controlled the Senate.

Others close to him say he has little trust in Maziarz and Republican leader Sen. Dean G. Skelos of Rockville Centre. Still, significant political challenges await Stachowski as a result of his decision to stick with his Democrats. The often-crucial Conservative Party line could hang in the balance as he prepares for what could be the fight of his political life in 2010.

Though they have historically supported Stachowski throughout his career, conservatives plan to ask plenty of questions before backing him again — even though Stachowski may sport the most conservative voting record of any Democrat in the Senate.

“Without question, he needs to take a strong stand for reform,” said Erie County Conservative Chairman Ralph C. Lorigo. “Whether he takes that position with his own Democratic group or the new group, he should do it.”

In addition, he can no longer expect Golisano, the billionaire owner of the Buffalo Sabres, to spend another $250,000 on his behalf, as he did in 2008. Stachowski fell out of favor after he joined his Democratic colleagues and voted for the tax-and fee-heavy 2009-10 budget.

The Independence Party line also seems problematic, since it is now essentially controlled in upstate by Golisano and Pigeon.

In the end, Stachowski said, “I just think that if you stay with your integrity, you’re better off.”