After President Joe Biden dropped out of the 2024 presidential race on Sunday afternoon, he endorsed Vice President Kamala Harris, who, according to recent polling data, is the strongest candidate to take on former President Donald Trump.

Biden announced his exit from the race in a letter to the American public posted on social media on Sunday following weeks of fighting between Democrats who wanted Biden to step down and those who thought he was the best choice for the party after his disastrous debate performance against Trump late last month.

With Biden out of the race, the Democratic Party must work fast to secure a new nominee by August 7. The Democratic National Convention (DNC) where the party’s nominee is named will take place in Chicago from August 19 to 22.

After the debate, polls started to give respondents other options than Biden for the Democratic nominee and asked them about hypothetical match-ups between those potential nominees and Trump. Harris has proven, so far, to be the best candidate to go up against Trump, except for the wild card, former first lady Michelle Obama. Not enough polling on Obama has been released to tell how she would fare against Trump, but she beat him in one recent poll.

Newsweek has reached out to Trump’s campaign and Harris’ press secretary via email for comment on Sunday evening.

Vice President Kamala Harris

In a CBS News/YouGov poll conducted from July 16 to 18, 51 percent of likely voters picked Trump, compared to 48 percent who chose Harris. The poll surveyed 2,247 registered voters and has a margin of error of plus or minus 2.7 percentage points.

In a Reuters/Ipsos poll conducted on July 16, Harris and Trump were tied at 44 percent of support among registered voters. The poll surveyed 992 registered voters and has a margin of error was plus or minus 3.3 percentage points.

Governor Josh Shapiro

Pennsylvania Governor Josh Shapiro has also been floated as a possible replacement for Biden.

In a poll conducted by Data for Progress, a left-wing think tank, conducted on June 28, Shapiro received 43 percent of the vote, but Trump still beat him with 46 percent. The poll surveyed 1,011 likely voters and has a margin of error of plus or minus 3 percentage points.

In the same poll, Harris received 45 percent of voter support and Trump got 48 percent.

Meanwhile, an Emerson College poll conducted between July 7 and 8, found Shapiro with only 38 percent of the vote while Trump got 46 percent. The poll surveyed 1,370 registered voters and has a margin of error of plus or minus 2.6 percentage points.

Harris did better than Shapiro in the Emerson poll as well, but did not beat Trump (43 to 49 percent).

Governor Gretchen Whitmer

In the same Emerson College poll, Michigan Governor Gretchen Whitmer also got 38 percent of the vote when up against Trump, but the former president did slightly better against Whitmer than Shapiro, getting 48 percent of the vote.

A Reuters/Ipsos poll conducted from July 1 to 2, found Whitmer with only 36 percent of the vote and Trump with 41 percent. The poll surveyed 892 registered voters and has a margin of error of plus or minus 3.5 percentage points.

Harris, meanwhile, got 42 percent of the vote against Trump’s 43 percent in the Reuters/Ipsos poll.

Governor Andy Beshear

In the July 1 to 2 Reuters/Ipsos poll, Kentucky Governor Andy Beshear got 36 percent of voter support when up against Trump who got 40 percent.

Governor J.B. Pritzker

Illinois Governor J.B. Pritzker did the worst out of the Democrats mentioned in the July 1 to 2 Reuters/Ipsos poll. He only got 34 percent of the vote compared to Trump’s 40 percent.

However, the governor did better in the Data for Progress poll where he received 43 percent of voter support compared to Trump’s 46 percent.

Governor Gavin Newsom

California Governor Gavin Newsom did slightly better than Shapiro and Whitmer in the Emerson College poll, getting 40 percent of the vote. However, Trump still beat Newsom in the match-up with 48 percent.

Meanwhile, in the July 1 to 2 Reuters/Ipsos poll, Newsom got 39 percent compared to Trump’s 42 percent.

In a more recent NPR/PBS News/Marist College poll conducted between July 9 and 10, Newsom does better with 50 percent of voter support, but still does not beat Trump who got 48 percent. The poll surveyed 1,174 registered voters and has a margin of error of plus or minus 3.3 percentage points.

Harris, meanwhile, also got 50 percent of the vote against Trump in the poll, but in their match-up, the former president got 49 percent.

Former First Lady Michelle Obama

Respondents in the July 1 to 2 Reuters/Ipsos survey were also asked about the former first lady. Obama was the only one to beat Trump (Biden tied with him at 40 percent). She got 50 percent of voter support compared to Trump’s 39 percent.