DETROIT — Senator Kamala Harris of California structures her stump speech around two themes — “truth” and “justice” — meant to evoke her career as a barrier-breaking prosecutor and cultivate a reputation as a fearless public advocate.
But when Ms. Harris swept into Detroit to address an N.A.A.C.P. banquet on Sunday night, she added something new. After her signature windup of “let’s speak truth,” she replaced her usual recitation of Democratic policies with an attack on President Trump, accusing him of enabling bigotry and divisiveness and refusing “to call neo-Nazi violence what it is: domestic terrorism.”
“This president isn’t trying to make America great,” she said, “he’s trying to make America hate.”
With that, Ms. Harris was nodding to a political truth: She is attempting to reset her campaign after stagnating in Democratic primary polls, using her strengths as a prosecutor — which were on display during a recent face-off with Attorney General William Barr — to mount a sharp indictment of Mr. Trump.
Ms. Harris entered the 2020 race in January seeking to make history as the first black female president, and drew 20,000 people to her campaign kickoff in Oakland and a burst of donations that helped her emerge as the No. 2 fund-raiser in the Democratic field through March. But from the start, she has found herself in a political vise, squeezed by competing factions in her party and even in her own campaign, which has led to some stumbles.
Ms. Harris is under pressure from liberal activists who are pushing Democrats toward newer, bolder horizons. She has repeatedly sought to placate the left since setting her sights on the presidency — an impulse many in her orbit say is reinforced by her campaign chair, Maya Harris, her sister.
At the same time, other Harris advisers and allies have winced at some of the senator’s overtures to liberals, such as calling for eliminating private health insurance and refusing to rule out letting prisoners vote, two comments she later modified. These supporters believe her pool of attainable voters sits squarely between center and left, and that she need not always offer the answer liberal activists may want from her.
These tensions, along with Ms. Harris’s instinct for caution, have slowed her candidacy. After initially focusing on a sweeping tax proposal aimed at lifting the poor and middle-class, she has turned to a teacher pay increase. Plans floated among her advisers earlier this year for a series of policy speeches and an embrace of free trade that could contrast her with progressive rivals like Senators Bernie Sanders and Elizabeth Warren have not come to fruition.
But two recent events — Ms. Harris’s insistent questioning of Mr. Barr at the Senate Judiciary Committee hearing last week, and Joseph R. Biden Jr.’s multiday spat with Mr. Trump — have been clarifying moments for Ms. Harris and her aides, demonstrating the value of elevating her voice of opposition to the president and seeking direct confrontation with the White House, according to her advisers. Her campaign is also drawing on internal polling of early nominating states showing that Democratic primary voters are consumed with defeating Mr. Trump.
Now, with Mr. Biden rising in some polls since entering the race and, for the moment, claiming some of the African-American voters she covets, Ms. Harris is recalibrating.
She capitalized on her interrogation of Mr. Barr, which went viral and was viewed online more than five million times, with a round of cable TV interviews and new investments in Facebook advertising. She lashed Mr. Barr as well as Mr. Trump again in her remarks to the N.A.A.C.P. on Sunday. And on Monday, after reading from an anti-bullying book to a classroom of Michigan schoolchildren, she said the message was instructive for the current occupant of the Oval Office.
“Let me tell you how much our president can learn from a fourth grader!” she said to laughter. “The president of the United States of America has a profound amount of power that comes with that microphone and bully pulpit. And we can no longer have a president that uses that microphone to divide.”
Ms. Harris sidestepped a question from The New York Times about her pivot toward Mr. Trump — “I’m running against President Trump because I think he should not be president,” she said — but her spokeswoman said the senator is eager to “prosecute the case’’ against Mr. Trump, invoking a phrase Ms. Harris has used intermittently.
“Going forward she is actively going to do that,” said Lily Adams, the spokeswoman.
Adversaries and allies alike are already paying attention.
Mr. Trump said on Fox News that she has “got a little bit of a nasty wit,” one of two times in a week he called her “nasty.” And by the time she arrived in Detroit, her exchange with Mr. Barr was preceding her.
“Don’t try to cover up because Kamala will sure enough make you choke up,” said the Rev. Wendell Anthony, the head of the Detroit N.A.A.C.P., who introduced Ms. Harris on Sunday.
Michelle Keeble, a Detroit teacher, said she trusted Ms. Harris because of the candidate’s new rallying cry against Mr. Trump. “The Democrats’ agendas are pretty similar, so show me how you’ll bring people together,” Ms. Keeble said.
Todd Rutherford, the South Carolina House minority leader, called Ms. Harris’s focus on Mr. Trump “a sound approach because that’s what people are interested in.” He added: “Be yourself because that’ll carry you further than trying to out-left the left.”
But political advice is more easily offered than followed in a presidential race, and Ms. Harris, Maya Harris and other advisers are hearing progressive voices that are just as forceful.
Ms. Harris has carefully navigated the currents of her party since she was first elected district attorney in San Francisco, avoiding confrontations with the left that could slow her ascent while keeping enough distance from her hometown’s famously liberal politics to retain her future viability.
Maya Harris, a former executive at the A.C.L.U., has deep ties to the left and has sought to tamp down criticism from outside allies while also courting them.
In one instance, she called A.C.L.U. officials after the publication of a critical op-ed written by a staff lawyer — who is a transgender man — about Kamala Harris’s record on L.G.B.T.Q. issues while she served as California attorney general.
In early April, Maya Harris organized a private meeting between the senator and several prominent voices in criminal justice advocacy, after consulting Michelle Alexander, the prominent civil rights author and a longtime friend of the family.
According to several people familiar with the discussions, Maya Harris has asked advice on how to deal with the campaign’s “messaging problem” among the party’s left, and with black activists in particular.
Last week, Ms. Harris and her sister met with DeRay Mckesson and Samuel Sinyangwe, two leading criminal justice activists who were co-founders of Campaign Zero, the group advocating police reform that was born out of the Black Lives Matter movement. Mr. Mckesson said the purpose of the meeting was to push the campaign to embrace a bolder vision of criminal justice reform.
Cliff Albright, a co-founder of Black Voters Matter Fund, said that despite recent overtures from Ms. Harris’s presidential campaign, she still has a “credibility gap” with the progressive community.
“Trust has to be built,” Mr. Albright said. “And she has to build and it has to be through substantive policy, and use policies that us activists have built. She doesn’t have to reinvent the wheel — she has to look to the organizing community that has been doing that work.”
This lobbying campaign from liberals is part of the reason Ms. Harris has embraced some controversial policies her Democratic rivals were championing, like Medicare for all and the impeachment of Mr. Trump; avoided taking a firm position on others when asked, such as prisoners’ voting rights and reparations for the descendants of enslaved black Americans; and eased away from hard-line elements of her California record, like prosecuting parents for truancy.
But such pressure is coming up against the advice of three top Harris consultants — Ace Smith, Sean Clegg and David Binder — who have extensively polled and run focus groups on the Democratic primary electorate and do not believe she should bow to activists. A recent survey of voters in early states and a handful of Super Tuesday states tested potentially negative aspects of her record as district attorney and state attorney general and found they did little damage to her standing, according to two officials briefed on the findings.
The three strategists have clashed with Maya Harris since the campaign got underway over whether to mollify the left, according to two Democratic officials familiar with the internal debate. The senator’s sister has been more eager to find common ground with liberal groups when possible, both to develop allies and to mitigate criticism.
“Maya has spent years working on these issues and has longstanding and deep relationships in this field,” said Rashad Robinson, executive director of Color of Change, a political advocacy group. He said Maya Harris played a similar role during Hillary Clinton’s 2016 campaign, serving as a connector between activists and the candidate. He has met with the Harrises twice since April. “Advocates know her and they know she has shared values.”
In a statement, Maya Harris did not dispute that there were differences in the campaign, but suggested she was hardly opposed to spotlighting her sister’s law enforcement record.
“Her career as a prosecutor makes her uniquely suited to take on a president who, frankly, doesn’t respect the law,” she said. “And it’s not just that she was a prosecutor — it’s that she’s a prosecutor who fought for justice, and equality her whole career and will as president.”
Ms. Harris’s tentativeness can be traced back to her history as a pathbreaking woman attempting to satisfy divergent constituencies, first in her ever-fractious city and then statewide. She has been whipsawed since she ran for district attorney against the death penalty and was then intensely criticized, including by Senator Dianne Feinstein, for not reversing course after a police officer was murdered shortly after she was sworn in.
But even some of her admirers say she needs to better grasp the nuances of this primary and the pragmatic nature of her would-be supporters who just want to eject Mr. Trump from the Oval Office.
“You’re not going to get to the left of Senator Sanders and nobody should try,” said Sue Dvorsky, a former Iowa Democratic chair.
Bonnie Malak, a teacher who saw Ms. Harris in Detroit, said that she plans to vote for Ms. Harris, but has been put off by the repeated clarifying, particularly on the question of voting rights for incarcerated persons.
“Did she not do her research?” Ms. Malak said. “That would seem like something she would not need to research.”
Ms. Harris’s allies note that she has overcome challenges in each of her past campaigns. But to do so on this stage, where the scrutiny is exacting and risk is required, she may have to anger or at least disappoint some factions of her party.
Confronting Mr. Trump, however, is unlikely to turn off any Democrat.
Yolanda King, a 44-year-old Detroit teacher who saw Ms. Harris speak Monday, said that as a black woman, she particularly likes it when Ms. Harris targets Mr. Trump.
“I’m not going to lie, it feels good when it’s someone who looks like me,” Ms. King said. “It feels like I’m looking in a mirror.”