These nominees are looking to become Commander in Chief.

With the presidential campaign season heating up, here are 10 of the leading candidates bidding for the chance to knock President Donald Trump from the White House.

Kamala Harris

Kamala Harris

Kamala Harris announcing her candidacy for President of the United States at Howard University on January 21, 2019

Kamala Harris, a freshman senator and former attorney general of California, boasts a resume tailor-made for the Democratic candidacy: She's championed core causes like tax cuts for the middle class, immigration reform and protection for Planned Parenthood, as well as progressive elements like the single-payer Medicaid-for-all healthcare system and marijuana legalization. Furthermore, as the second African-American woman and first South Asian in the Senate, she represents the party's push to embrace diversity. Those itching for a fight with Trump can take comfort in Harris' formidable presence on the Senate Judiciary Committee, and her prosecutorial background embellishes her reputation for toughness, though that same background has left her open to scrutiny about some of her contrasting actions as attorney general.

Cory Booker

Cory Booker

Cory Booker delivering remarks on the first day of the Democratic National Convention on July 25, 2016, in Philadelphia, Pennsylvania

Like Harris, Cory Booker is seeking to become the second African-American president and, like the first, he possesses a gift for oratory infused with visions of unity and hope. Booker has been in the public eye since becoming a Newark city councilman at age 29 and then the city's mayor, his star growing through his early embrace of Twitter and good Samaritan feats like rescuing a neighbor from a burning building. In the Senate, he's probably best known for attention-grabbing questions on the Judiciary Committee, though he did score a legislative victory by co-sponsoring a criminal justice bill in 2018. With his rock star status and embrace of the party’s popular progressive stances, he's among the early favorites in the field.

Elizabeth Warren

Elizabeth Warren

Elizabeth Warren acknowledging the crowd on the first day of the Democratic National Convention on July 25, 2016, in Philadelphia, Pennsylvania

Elizabeth Warren was one of the first major Democratic figures to announce her candidacy, underscoring her readiness to jump in the fray. With a clearly articulated agenda as a fighter for the middle class, the Massachusetts senator has introduced an ethics bill, proposed a billionaire tax and floated a constitutional amendment to guarantee voting rights. She also supports Medicaid-for-all and the Green Deal and has upped the ante on shutting out major donors from the political process. Undoubtedly one of the party's firebrands, she's also been dogged by lingering discomfort over her claims to Native American ancestry, an issue certain to remain in the news cycle as long as President Trump has access to Twitter.

Bernie Sanders

Bernie Sanders

Bernie Sanders speaking to campaign volunteers during an event at Five Sullivan Brothers Convention Center January 31, 2016, in Waterloo, Iowa

What a difference four years makes. Heading into 2016, Bernie Sanders was the grassroots outsider who struck a chord with his calls for tuition-free public universities and eradicating big-money donors from politics. Now, the Vermont senator is the standard bearer for the Democratic Party's leftward march (even if technically an independent). Many of the major Democratic candidates have lined up to back his Medicaid-for-all healthcare system, while other proposals, like a $15 per hour minimum wage, have gone mainstream. Questions remain about his foreign-policy agenda, along with whether the party wants to turn to a younger generation of leadership. 

Kirsten Gillibrand

Kirsten Gillibrand

Kirsten Gillibrand delivering remarks on the first day of the Democratic National Convention on July 25, 2016, in Philadelphia, Pennsylvania

Kirsten Gillibrand has come a long way since her early days as a congresswoman from a conservative New York district. Once known for her support of gun rights and opposition to same-sex marriage, she has since embraced such liberal causes as Medicaid-for-all and abolishing the Immigration and Customs Enforcement agency (ICE). On her own, Gillibrand has emerged at the forefront of women's and family issues in the Senate by spearheading a universal paid family leave program and seeking to hold the military accountable for sexual harassment claims. More recently, she called on former colleague Al Franken to resign after accusations of improper behavior surfaced in late 2017. 

Amy Klobuchar

Amy Klobuchar

Amy Klobuchar announcing her presidential bid on February 10, 2019, in Minneapolis, Minnesota 

Now in her third term as a Minnesota senator, Amy Klobuchar has presented herself as a moderate alternative to the increasingly progressive elements of her party. She has not joined the chorus clamoring for Medicaid-for-all, though she has highlighted climate change and income inequality as important issues. Furthermore, she boasts a formidable track record for getting things done with her focus on bipartisan policies to rein in the cost of prescription drugs and protect online privacy. Klobuchar will likely forge more of a connection to heartland voters than the coastal elites of her party, though her claims to being "Minnesota nice" have been undermined by reports of nastiness toward her staffers.

John Hickenlooper

John Hickenlooper

John Hickenlooper delivering remarks on the fourth day of the Democratic National Convention on July 28, 2016, in Philadelphia, Pennsylvania

Among the next tier of recognizable names, former Colorado governor John Hickenlooper also stands as a decided moderate in a progressively charged field. Noting the terrible "division" of the country, Hickenlooper points to his record as chief executive of a purple state as evidence of his ability to solve problems. Indeed, he not only pulled off the balancing act of passing gun control laws in a divided legislature, but he also established a model for recreational marijuana regulation that left Colorado with a booming economy by the end of his second term. Environmentalists have taken aim at his record, but Hickenlooper seemingly holds an ability to peel away some Trump votes with his pro-business chops.

Jay Inslee

Jay Inslee

Jay Inslee addressing the crowd during a launch event for the Bezos Center for Innovation at the Museum of History and Industry on October 11, 2013, in Seattle, Washington

Another lesser-known governor from the West, Jay Inslee raised his profile heading into the campaign cycle by serving as chairman of the Democratic Governors Association and his frequent appearances on the cable-news circuit. He has far more in common with the progressives than he does with Hickenlooper, promoting a platform for gun restrictions, gay rights, spending on education, job training, and healthcare. He's also sought to angle himself as the leading proponent for climate-change policy, arguing that the issue is "connected to virtually every other value system," though he had mixed results in that department with Washington voters and lawmakers.

Julián Castro

Julian Castro

Julián Castro announcing his candidacy for president in 2020 at Plaza Guadalupe on January 12, 2019, in San Antonio, Texas

Like Booker, Julián Castro first made his mark as the youngest person elected to the San Antonio city council and then the city mayor, though his path took him to the Obama administration as secretary of Housing and Development and not the Senate. The son of an activist, Castro has portrayed himself as a Latino success story and the "antidote" to Trump's harsh rhetoric on immigrants. Along those lines, he's promoting a family theme, hailing his grandmother's work in raising him and naming his twin brother his campaign manager. On the issues, he espouses an agenda of comprehensive immigration reform, environmentalism and education, notably the introduction of a universal pre-kindergarten program.

Beto O'Rourke

Beto O'Rourke

Beto O'Rourke during a campaign rally at the Pan American Neighborhood Park November 4, 2018, in Austin, Texas

A later entry to the race, Beto O'Rourke announced his candidacy a few months after his narrow loss to Ted Cruz for a Senate seat from deep-red Texas. A former three-term congressman from El Paso, the skateboarding O'Rourke packs a rock star persona to match those of Booker and Harris and his small-donor network is second only to that of Sanders. However, unlike the others, the Texan embarked on his campaign without a fully defined platform. He has made steps in that area, releasing a 10-point immigration plan and stressing a focus on climate change and criminal justice reform, though he has also delivered mixed messages about pet progressive issues like abolishing ICE.