WASHINGTON >> It was not enough for Sen. Harry Reid to just dismiss Republican offers as "vexatious" or "kid’s stuff" or "one cockamamie, can’t-pass idea after another." He called the White House and asked it to issue a veto threat, which it promptly did.

It was not enough for Reid, the Senate majority leader, to accuse his counterpart in the House, Speaker John A. Boehner, of being dragged around by a tribe of rogue "banana Republicans." He leaked a series of emails between their offices in an attempt to humiliate the speaker.

With Congress locked in an intractable budget dispute that kept the federal government shut down for a second day Wednesday, Reid is not only acting as the public face of the no-compromise posture of Democrats on Capitol Hill, he is the power behind the scenes driving a hard-line strategy that the White House and congressional Democrats are hoping will force Republicans to crack.

His tactics have been unapologetically aggressive, even when measured by the fast and loose rules of engagement in a political climate so bitterly polarized.

Advisers and Senate colleagues say that Reid, of Nevada, who at 73 is more wily and scrappy than his stooped posture and shuffling walk suggest, is animated and outraged to a degree they have rarely seen in his 25 years in the Senate. And unlike previous high-stakes budget talks — when he was eclipsed by Vice President Joe Biden and Sen. Mitch McConnell, R-Ky., the minority leader — Reid is now in command.

Though he has faced seven years of Republican attempts to frustrate his agenda at every turn, this latest fight, which he believes could have been stopped if the party’s leaders had only stood up to their more junior members, has convinced him that he has no viable Republican partners on either side of the Capitol.

Reid’s passion and pique come from his conclusion that this fight is about something more fundamental than spending resolutions.

"He is not going to let this crisis make us give away something that is part of what we believe in," said Sen. Patty Murray, D-Wash., and a member of Reid’s leadership team. "He feels passionately that if we allow our country to be run by hostage-taking — ‘I feel passionately about an issue, and I’m going to shut down the government unless I get my way’ — it is bad for today, it’s bad for tomorrow, it’s bad for democracy."

Reid’s tendency to speak without inhibition or filter has created no shortage of complications and may have so alienated Republicans that they see no incentive to work with him. On Wednesday, Republican press offices, including Boehner’s, and Tea Party groups circulated remarks from Reid in which he appeared to be dismissive of cancer-stricken children. (In fact, he was ineloquently making a point about the need to fund the entire government, not just parts that Republicans have selected for special appropriations bills as a way to ameliorate the effects of the shutdown.)

Reid’s strategy to break Republicans depends on keeping his caucus unified, which is no small feat in a party as Balkanized as the Democrats can be. His colleagues said he understood all along that the only way Democrats could come out on top in a spectacle as politically harmful as a government shutdown was if they held together. With negotiations continuing, Reid declined to be interviewed.

So far, he is the only leader in Congress not to lose any of his members as the pressure rises. McConnell and Boehner, of Ohio, are both facing resistance from Republicans who represent states that have a mix of conservative and liberal voters. Rep. Nancy Pelosi of California, the Democratic leader in the House, has also lost some members of her conference who hail from Republican-leaning districts and are reluctant to appear as if they are siding with President Barack Obama.

"From the first time we talked about this, he said, ‘We are not giving in,’" said Sen. Charles E. Schumer, D-N.Y., who is one of Reid’s top lieutenants. "He had an instinctive understanding that this would work as long as Democrats didn’t fall for the bait. We haven’t, and we won’t."

But Reid is more than a smart strategic thinker, Schumer added: "Harry is a tough guy, and if you cross him he won’t forget it."

Reid rebuffed McConnell last week after the Republican leader called him and urged him to try to strike a compromise with Boehner. His firm answer was no. Though Reid did meet with Boehner, McConnell and Pelosi on Wednesday at the White House, he had initially persuaded the president not to hold a similar meeting last week because he was concerned it would appear too accommodating.

Reid, no one’s idea of a polished, pressed and scripted Washington politician, seems to relish playing such an aggressive hand.

At no point was this more evident than this week, when Reid’s office leaked a trove of emails between its staff and Boehner’s to Politico, a website and newspaper devoted to political coverage.

The release of the emails, sanctioned by Reid, was an attempt to embarrass Boehner for publicly supporting the elimination of health care subsidies for members of Congress and their staffs despite the fact that he and his advisers had privately negotiated a deal to preserve those benefits. The deal later fell apart. The move infuriated Boehner’s aides, who said they found it particularly destructive coming in the middle of a policy fight that will ultimately have to involve Republicans in some way.

"I’m sure he’s very proud of himself," Kevin Smith, Boehner’s communications director, said of Reid.

Those close to him say that when Reid says things about Republicans like "they have lost their minds," he means it. He has stood on his podium on the Senate floor every day this week and vowed to not negotiate with Tea Party "anarchists" and "extremists," despite advice from his advisers that the word "unreasonable" polls better with voters.

Reid’s upbringing in tiny Searchlight, Nev., where he grew up in a shack, is never far from his mind, even when he is speaking from his mahogany desk in the Senate chamber.

"He is unique in this city," said Jim Margolis, a longtime adviser. "And you see it in so many different ways. Is he the best TV talking head? No. He’d be the first to tell you that. Should he smile more? Yes. Should he say goodbye on the phone when he’s done talking to you? Probably. But those are things you’d assume are part and parcel of a polished figure in Washington. That is not Harry Reid."

© 2013 The New York Times Company