The Georgia House passes a sweeping bill to restrict voting, after dialing back a few measures.

Representative Zulma Lopez, whose district on the outskirts of Atlanta contains a majority of voters of color, said the bill would have an outsize impact on voters of color. In her district, she said, the number of drop boxes would be reduced to nine from 33. This was partly the result, she said, of Democrats’ being excluded from discussions.

“Close to 2.5 million Democrats voted in the general election in 2020,” Ms. Lopez said. “Yet Democrats in this House were left out of any meaningful input into the drafting of this bill.”

On Thursday, President Biden joined Georgia Democrats in denouncing Republican efforts to limit voting, calling conservatives’ efforts around the country “un-American.”

“I’m convinced that we’ll be able to stop this, because it is the most pernicious thing,” Mr. Biden said at his first formal news conference. “This makes Jim Crow look like Jim Eagle. I mean, this is gigantic, what they’re trying to do. And it cannot be sustained.”

He vowed to “do everything in my power, along with my friends in the House and the Senate, to keep that from becoming the law.”

Alan Powell, a Republican representative from northeast Georgia, defended the state’s bill, saying it would bring needed uniformity to an electoral system that was pushed to the brink last year.

“The Georgia election system was never made to be able to handle the volume of votes that it handled,” he said. (Multiple audits affirmed the results of Georgia’s elections last year, and there were no credible reports of any fraud or irregularities that would have affected the results.) “What we’ve done in this bill in front of you is we have cleaned up the workings, the mechanics of our election system.”

“Show me the suppression,” Mr. Powell said. “There is no suppression in this bill.”

Thomas Kaplan contributed reporting.