Democratic presidential candidate Sen. Amy Klobuchar (D-Minn.) speaks during New Hampshire's state Democratic Party convention on Saturday in Manchester, N.H. (Robert F. Bukaty/AP)
Opinion writer

MANCHESTER, N.H. — If, as billed, New Hampshire’s Democratic state convention had its largest turnout ever this year, then the party surely has President Trump to thank. Kicking off the proceeding on Saturday morning, Democratic National Committee Chairman Tom Perez quoted Trump’s galling assertion that “you have no choice but to vote for me." He brought the crowd to its feet when he retorted, “We’ve got no choice but to get his ass out of the White House!” It was that kind of day.

A close second in the villain department was Majority Leader Sen. Mitch McConnell (R-Ky.), whose name evoked boos whenever mentioned, as if he were the crowd’s Haman, the villain who is ritually denounced at Jewish Purim celebrations. “Moscow Mitch” chanting broke out in the midst of Rep. Chris Pappas’s (D-N.H.) speech, to Pappas’s delight. “You know he hates that,” he said with a grin.

Outside, throngs of supporters filled the sidewalk and the plaza in front of the Southern New Hampshire University Arena, waving signs, chanting for their candidate and donning their campaign’s T-shirt. Supporters of Sen. Elizabeth Warren (D-Mass.) outnumbered other camps — by a lot.

As enthusiastic as some Democrats are for their particular candidate, the message inside was “unity.” Sen. Jeanne Shaheen (D-N.H.), who faces a tough reelection campaign, drew a sustained ovation when she exhorted the crowd to support whoever the nominee might be. That theme was repeated throughout the day. Whether that spirit survives next week’s debate is an open question.

The contrast between former vice president Joe Biden and the best of the rest was stark.

Biden got the first slot for presidential candidates. In a speech that was largely a rehash of his stump speech — vowing to repair the middle class, excoriating Trump for having “unleashed the deepest, darkest forces,” promising to triple spending for Title I, etc. — his most memorable line was a slip of the tongue, referring to Trump as “Donald Hump." The crowd laughed good-naturedly. Biden dryly observed, “Freudian slip.”

He also added a new turn of phrase. “I refuse to postpone,” he said. “I refuse to postpone one more day to take back our country.” It was a workmanlike effort, but Biden did not generate the same enthusiasm as the candidates who followed him, starting with Sen. Cory Booker (D-N.J.).

Booker was greeted with a more raucous welcome, and his energetic, inspirational message was rewarded with multiple ovations. Given his performance here and elsewhere on the stump, it remains something of a mystery why Booker’s poll numbers are stuck in low single digits. In listing his top priorities, among them health care as a right and access to good education for all children, he repeated the refrain “We will rise!” after each policy item to great effect. Booker has not been able to build a campaign that can channel his considerable rhetorical skills into a winning message. Perhaps in town halls and living rooms next year he can catch fire in the weeks leading up to the Iowa caucuses and New Hampshire primary.

South Bend, Ind., Mayor Pete Buttigieg had a huge contingent of supporters inside the arena and got the most enthusiastic greeting of the morning. His focus was on the generation that will follow the millennials, painting a picture of the problems facing 12- and 13-year-olds, including school shootings, health care and climate change.

“Pragmatic and values-driven leadership is what mayors do every day,” he said. “We need more of that in Washington, D.C.” His emphasis was on results-oriented lawmaking, a reminder that while, staunchly progressive, his technocratic problem-solving approach may draw moderates, should Biden falter. His biggest applause came when he promised to appoint an education secretary who actually believes in public education and a leader of the Environmental Protection Agency who believes in climate change. Buttigieg’s defense of his modified vision for Medicare-for-all was emphatic, including an argument for giving people a choice about their health care, and was made in terms that disgruntled Republicans could warm to. He may be the most effective voice to take on the two biggest proponents of government-run universal health care, Warren and Sen. Bernie Sanders (I-Vt.).

Sen. Kamala D. Harris (D-Calif.) got a warm, prolonged welcome. The chant “You gotta go!” from her supporters rang out after her first mention of Trump. She knows how to deliver a speech, when to raise her voice, when to drop her voice and when to wait for the applause. She exclaimed, “We are up for a good fight!” The audience roared.

She denounced Trump’s call to “Make America Great Again,” asking to what point Trump wanted to turn back the clock — Before the Voting Rights Act? Before the Civil Rights Act — and declared, “We’re not going back!” the audience cheered her wildly. “The only thing he manufactures is crises,” she declared. With the number of conflicts around the world, she said, that’s about the only thing “made in America.” The stump speech may be awfully familiar to those who follow the campaign day by day, but by mixing optimism, inspirational rhetoric and feisty barbs, Harris conveys a sense of emotional empathy, as if instead of giving a speech, she’s just chatting with a few girlfriends. (You know Trump is golfing again?)

Harris mentioned her “3 a.m. agenda,” the purpose of which was not the details but to remind voters that she knows people are up late worrying about their families. Better than any candidate, she is able to channel voters’ anger at and contempt for Trump, as well as their thirst for “something better than this.”

Sen. Amy Klobuchar (D-Minn.) brought her A game, displaying her familiarity with New Hampshire and identifying with its spirit of independence. She’s a better candidate and speaker, staying punchy and upbeat, than her poll numbers reflect. Her message is clearly aimed at a coalition of Democrats, independents and alienated Republicans. She declared, “I don’t want to be the president for half of America. I want to be the president for all of America!” She has picked up some catchy lines, “If millionaires can refinance their yachts,” she declared, students should be able to refinance their loans.

Klobuchar is more energetic and forceful in venues such as this than on the debate stage. “I’m tired of a whiner in the White House” got big applause, as did her line that she’d never have her vice president stay at a resort she owns: “Oh, that’s right, I don’t own a resort!” She’s another candidate who has had a tough time fighting for the spotlight in a crowded field, but one who still has a shot if she gets hot at the right moment in the weeks before Iowa. Her issues agenda — from broadband in rural areas to ending the tariff war — is well suited to a farm state.

We’ll have more on the afternoon proceedings tomorrow.

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