WASHINGTON — Democrats in the House are set to vote Thursday on a far-reaching policing overhaul after the collapse of a Senate GOP effort to address the global outcry over the deaths of George Floyd and other Black Americans.

House Speaker Nancy Pelosi, D-California, gathered with members of the Congressional Black Caucus on the Capitol steps, challenging Congress not to allow the deaths to have been in vain or the outpouring of public support for law enforcement changes to go unmatched. Yet even with passage, the prospects for changes are dim, for now.

She said the Senate faces a choice “to honor George Floyd’s life or to do nothing.”

The Thursday evening vote sends a signal with the George Floyd Justice in Policing Act, perhaps the most ambitious proposed changes to police procedures and accountability in decades. Backed by the nation’s leading civil rights groups, it seeks to match the moment of street-filled demonstrations. It has almost zero chance of becoming law.

On the eve of the vote, President Donald Trump’s administration signaled he would veto the bill. And Senate Majority Leader Mitch McConnell has also said it would not pass the Republican-held chamber. After the GOP policing bill stalled Wednesday, blocked by Democrats, Trump shrugged.

“If nothing happens with it, it’s one of those things,” Trump said. “We have different philosophies.”

Congress is now at a familiar impasse despite protests outside their door and polling that shows Americans overwhelmingly want changes after the deaths of Floyd, Breonna Taylor and others in interactions with law enforcement. The two parties are instead appealing to voters ahead of the fall election, which will determine control of the House, Senate and White House.

Lawmakers who have been working from home during the COVID-19 crisis were summoned to the Capitol for an emotional daylong debate. Dozens will vote by proxy under new pandemic rules. During the day, Democratic lawmakers read the names of those killed at the hands of police, shared experiences of racial bias and echoed support of Black Lives Matter activists.

Both of Maine’s Democratic U.S. representatives, Chellie Pingree of the 1st District and Jared Golden of the 2nd District, support the bill. Golden, who represents a swing district, announced that he was voting for it in a Thursday statement. He said he strongly disagrees with calls from activists to defund police while saying “racism and inequality” must be addressed.

“The bill today provides law enforcement officers with more training, not less, while reinforcing our commitment to shine a light on bad actors and on any instances of unacceptable negligence, unjustified violence, or racism,” he said.

Both bills share common elements that could be grounds for a compromise. Central to both would be the creation of a national database of use-of-force incidents, which is viewed as a way to provide transparency on officers’ records if they transfer from one agency to another. The bills would restrict police chokeholds and set up new training procedures, including beefing up the use of body cameras.

The Democratic bill goes much further, mandating many of those changes, while also revising the federal statute for police misconduct and holding officers personally liable for damages in lawsuits. It also would halt the practice of sending military equipment to local law enforcement agencies.

Associated Press writers Lisa Mascaro, Laurie Kellman, Andrew Taylor, Darlene Superville and Jill Colvin and Bangor Daily News writer Michael Shepherd contributed to this report.