President Joe Biden’s abrupt withdrawal from the 2024 presidential race raised more questions than it provided answers. Here are some:

That’s easy. Top aides finally convinced him he couldn’t win. Trailing former President Donald Trump all year, Biden’s prospects never recovered from his disastrous performance in the June 27 debate that his team erroneously thought could jump-start his campaign.

Almost certainly, no. In two days, she secured enough delegate commitments to clinch the nomination after most top Democrats quickly joined Biden in backing her. West Virginia Sen. Joe Manchin, who switched his registration to independent, talked vaguely of the need for a process appealing to independents, but decided not to run. The Democrats are adopting rules for the 4,000 elected delegates to formally pick the nominee by Aug. 7. Though committed to Biden, they are free to vote for anyone.

Some Republicans are threatening legal challenges on grounds the delegates were elected to support Biden. But nominations are up to the political parties, and the Democrats had never formalized Biden’s nomination.

She moved fast right after Biden’s announcement, methodically lining up support from key individuals and constituencies. The Biden-Harris Committee is now The Harris Committee, the campaign apparatus is hers, and the money flow, which had dried up, resumed with a flood of dollars, raising an amazing $81 million in just 24 hours.

In a speech to campaign workers Monday, she showed how she will use her prosecutor’s background to criticize Trump and outlined her vision of ways she hopes to help the middle class.

That may be old news. Admittedly, she was a poor campaigner when she sought the 2020 Democratic nomination, stumbling over complex issues like Medicare for All. But she was a pretty good debater, a valuable presidential campaign asset.

She struggled at the outset to find her role as vice president but found her voice after the Supreme Court reversed its prior approval of abortion rights and opened the way for Republican-led states to ban or restrict abortions. She’ll face far closer scrutiny running for president than running for vice president, but Monday’s speech was a good start.

A big one, as it was for Biden. Maybe bigger. Biden initially assigned her to deal with the Central American roots of the influx of illegal immigrants into the United States. She stumbled in public discussion of the issue, and Republicans pounced, magnifying her actual role, incorrectly calling her the “Border Czar” and blaming her for the administration’s failures. She has since moved on to other issues, like women’s rights, but can expect renewed GOP focus on immigration, which Trump considers one of his best issues, as it was in 2016.

A white male in elective office with a moderate reputation.

One obvious candidate: Arizona Sen. Mark Kelly, 60, a former Navy pilot and astronaut married to former Rep. Gabby Giffords, who was seriously wounded in a 2011 assassination attempt and has since become a leading spokeswoman for increased gun control. Arizona is an important swing state, as is neighboring Nevada.

Gov. Roy Cooper of North Carolina, 67, is highly regarded but little known. Cooper is a former state attorney general like Harris, now completing his second term as governor. He has experience tussling with Republicans in the closely divided state.

Gov. Andy Beshear of Kentucky, 46, is another former attorney general who twice won the governorship in what has become a very Republican state.

Gov. Josh Shapiro of Pennsylvania, 51, is another former attorney general who was elected two years ago. He is the only Jewish contender. Pennsylvania may be the single most crucial battleground state in the election.

The biggest question of all. The answer: It is too soon to tell.

Like Biden, Harris starts out as an underdog in a race where recent polls showed Trump’s advantage in key states increased after last month’s debate and may get a bounce from the Republican National Convention.

Scattered polling showed Harris might be stronger than Biden, but any true measure of their current strengths awaits her first appearances as the presumptive nominee. She may surpass Biden among younger voters, minorities and women in general, but is unlikely to poll as strongly among white males as Biden and could encounter problems in the crucial Rust Belt states.

Harris, 59, provides the age contrast with Trump, 78, that many voters sought when faced with a Biden-Trump rematch. She proves a strong debater against the former president. And Trump turns off independents by overdoing the personal attacks on Harris, who is the first Black woman and first with South Asian roots to hold national office. That could enable her to restore enough of the Democratic coalition that helped elect Biden and former President Barack Obama.

She is as poor a campaigner as when she sought the 2020 nomination. She struggles to defend the administration’s record, especially on immigration. Picking a moderate running mate fails to moderate her liberal image.

The United States elected a Black president (Obama) but has never elected a woman. What about a woman of color?

Carl P. Leubsdorf is the former Washington bureau chief of the Dallas Morning News.