PHOENIX — When Kyrsten Sinema began her rise in Arizona politics in the early 2000s, she was a Ralph Nader supporter and local spokeswoman for the Green Party who worked to repeal the death penalty and organized antiwar protests after the Sept. 11 attacks.
But today, as the Democratic nominee for Senate from Arizona in one of the most pivotal races in the country, Ms. Sinema is campaigning as an altogether different person. While she is now a three-term member of Congress, Ms. Sinema is running as much on her biography — her three years spent homeless as a child — as on any issue. She is using that personal hardship to project grit and distinguish herself from “most people in politics,” as she says.
This emphasis on her life story has had a dual effect: It has highlighted her lack of a strong political identity and it has drawn scrutiny to her story of homelessness and some contradictory elements in it.
Ms. Sinema’s evolution reflects a calculation about what it takes to prevail statewide in Arizona, which has not elected a Democrat to the Senate since 1988. And it is a strategy that has put her in a competitive position against Representative Martha McSally, her Republican opponent, as they both seek to replace outgoing Senator Jeff Flake, and Democrats try to upend the current one-seat G.O.P. majority in the Senate.
To the frustration of many Arizona progressives, Ms. Sinema has shifted from a firebrand — she told The Arizona Republic in 2003 “that the real Saddam and Osama lovers were Ronald Reagan and George H.W. Bush” — to membership in the congressional Blue Dogs, the most conservative group of House Democrats. Last year, she joined a small group of Democrats to back a bill that was promoted by President Trump and named for a woman killed by an undocumented immigrant, which would significantly stiffen penalties on migrants who illegally re-enter the country.
In her current race, Ms. Sinema holds up Senator Joe Manchin III, a centrist Democrat from West Virginia, as one of her role models; goes to lengths to avoid criticizing Mr. Trump; and is focusing on priorities for veterans and law enforcement. She has featured her Marine-turned-police-officer stepbrother in one ad; another shows machine gun-equipped helicopters, aircraft carriers and images of troops high-fiving. “Security and strength,” the announcer intoned, “whatever it takes.”
“What she’s always been is not a centrist or a bold progressive but an opportunist,” said Tomas Robles, an immigration activist who says Ms. Sinema won’t meet with his group. “She’s very smart about what the political climate is and where she wants to make next move.”
Her careful positioning was on display recently when — unlike every other Democrat in Arizona’s congressional delegation — she refused to back her party’s nominee for governor, David Garcia. Ms. Sinema is uneasy about being identified with Mr. Garcia because he has taken a far more liberal approach to immigration issues than she has, Arizona Democrats say.
The 42-year-old lawmaker’s metamorphosis began when, after a failed bid for the state legislature as a Green Party-aligned independent candidate, she won a statehouse seat as a Democrat in 2004. In the state Capitol, she began working with Republicans and found success — and attention — by forging bipartisan coalitions.
“We were both pretty progressive, but she learned along the way that to get things done you have to work across party lines and find common ground,” said David Lujan, a former Arizona House Democratic leader and a close friend of Ms. Sinema. He cited her ability to reach out to conservatives as part of a strategy that she devised to sink a 2006 ballot measure to define marriage as between a man and a woman.
Lauren Kuby, a liberal city councilwoman in Tempe, emphasized that Ms. Sinema is “a solid progressive” on many issues. But Ms. Kuby was blunt about what was behind the evolution.
“Kyrsten has always had her eyes on a larger electorate,” she said, acknowledging “the driver being ambition.”
Ms. Sinema herself has acknowledged her changing approach. In her 2009 book, “Unite and Conquer: How To Build Coalitions That Win and Last,” she argued that pragmatism was necessary to make progressive gains.
But with few major legislative accomplishments to her record, both Democrats and Republicans say, Ms. Sinema is largely running on a political image that she has shaped and reshaped over the years. And nothing is now more central to it now than her childhood homelessness.
In speeches and interviews, Ms. Sinema recalls how she spent three years as a child living in a former gas station “without running water or electricity.” She has highlighted that hardship as a way to distinguish herself from “most people in politics,” and she would be the rare senator with personal experience of being homeless.
But court documents reviewed by The New York Times raise questions about Ms. Sinema’s descriptions of what she endured in the mid-1980s, when her mother remarried and moved the family from Arizona to Florida. And Ms. Sinema herself, as her national profile has risen, has given contradictory answers about her early life.
In 1984, Ms. Sinema’s family sought a new start in the small Panhandle community where her stepfather, Andy Howard, had roots: Defuniak Springs, north of the Gulf of Mexico but far from the resorts and waterfront summer homes where wealthy Southerners vacation.
At first, her stepfather only found part-time work as a computer science teacher, so the family of five — Ms. Sinema, her mother, her stepfather and her two siblings — moved into what had been built as a service station in 1972 on a rural road. The building still stands today and is vacant.
In filings from 1985 and 1986 to the judge who handled her parents’ divorce, Ms. Sinema’s mother and stepfather outlined monthly payments they made for an electric bill, phone bill and gas bill while living in the former gas station, which was owned by her stepfather’s parents, according to the records reviewed by The Times. The stepfather’s grandparents lived in a farmhouse nearby.
“We are unable to provide adequately for the children,” Mr. Howard wrote to the court, noting that in the following month his “bills will exceed $2,000 and I will only bring in $1,500.”
Ms. Sinema, in an interview, would not directly address her family’s payments for the electric, phone and gas bills, but talked broadly about her description of homelessness. “Being homeless is when an individual or family are living in a situation that’s not really stable, when you’re living in a place that’s not meant for living in,” she said.
As for why her stepfather listed those payments for power, gas and a phone if they had no electricity, Ms. Sinema paused. “Oh gosh, I don’t have an answer for that,” she said. “That’s not something a little kid would hear about from her parents.”
Asked twice whether she had ever embellished details about her childhood, Ms. Sinema paused and did not answer directly. “I’ve shared what I remember from my childhood. I know what I lived through,” she said.
In this and other interviews on her homelessness, a pattern emerges: Ms. Sinema often includes vivid details, some that contradict other accounts. In 2013, she told the Washington Post the family had a toilet, but when pressed by the newspaper, she could not explain how it was flushed with no running water. And in a 2016 Arizona Republic story, she challenged the assertion of the previous owner of the gas station, who said that it had a spigot and wood-burning stove.
What is not in doubt is that Ms. Sinema and her family were living in deeply trying circumstances, relying on assistance from the local Mormon Church to which they belonged.
Yet Ms. Sinema’s unreserved statements about being homeless, and the public records pertaining to her upbringing, are noteworthy in part because of Ms. Sinema’s own views about the importance of candor and speaking precisely in public life.
She has scolded House Speaker Paul D. Ryan for apparently misstating his marathon time. She turned the importance of honesty into a section, called “Truth,” of her 2009 how-to book on political organizing, and said “sometimes I’m too honest.” She also writes that she is “a big fan of honesty” and adds that “it’s also wrong to tell half-truths and be sneaky about the truth — no doubt about it.”
The Times sought interviews with Ms. Sinema’s family members to discuss her experiences with homelessness. Her mother twice hung up on a reporter. In an email, her stepfather, Mr. Howard, said they were “proud of” her accomplishments but otherwise requested privacy.
Separately, Ms. Sinema’s campaign provided a statement from her stepfather and mother saying they lacked power and water. But asked in a subsequent email about why he would have been paying electricity, gas and telephone bills, Mr. Howard did not respond.
In a Washington Post story last month, her step-aunt said of Ms. Sinema’s account: “I realize this tugs at people’s heartstrings and that was what she was going for, but, you know, it’s not the truth.”
For Ms. Sinema, who has labored in the minority since coming to Congress, her Horatio Alger-like story is as crucial to her campaign as anything from her relatively short tenure in Washington. Having faced no serious primary on her left, she has run one of the most moderate-sounding and cautious Senate campaigns this year, keeping the media at arms-length and avoiding controversial issues.
Eventually, Ms. Sinema’s stepfather and mother found more work and a measure of financial stability. With the Mormon leader at their local church helping with a mortgage, the family left the gas station in 1987 and moved into farmhouse in the county.
And there were few brighter and more ambitious schoolchildren in the county than his stepdaughter, Ms. Sinema.
By 16, she had earned enough high school credits to graduate — and she did, as valedictorian. A prestigious scholarship to Brigham Young University in hand, she would go on to finish her undergraduate work in two years and then return to Arizona to work as a social worker.
She put Florida behind her, beginning her rise in politics with the Green Party and then as a progressive Arizona Democrat and now as a centrist House member. The Florida years became part of her narrative, and never more so than now.
“A number of years ago I started telling some of my friends, some folks I worked with, about my childhood. It was difficult,” she told The Times. “But what I found is it was very meaningful to them and it mattered to them. It helped people understand what motivates me, why I care so much about the stuff I care about. I think it helps people understand what drives the work that I do.”