NEW YORK TIMES, CATIE EDMONDSON

The House will vote this week on the Democrats’ signature piece of legislation, a sprawling compendium of ballot access, campaign-finance transparency and anti-corruption proposals devised to restore public trust in government.

The sweeping measure — as much a campaign platform as an actual piece of legislation — is intended to show the voters who catapulted Democrats into the majority that they are following through on their campaign pledges. The bill, nearly 700 pages, aims to dismantle barriers to voting, end big money in politics and impose stricter ethics rules on federal officials.

“This is about instilling the confidence of the American people in the political process, in what happens in government, that it is the people’s interests that are being served,” Speaker Nancy Pelosi said.

But Republicans arguably have spent more time trying to define the bill — called the For the People Act or H.R. 1, to underscore its primacy — and tear it down than Democrats have spent trying to promote it. Senator Mitch McConnell of Kentucky, the majority leader, has branded it the “Democrat Politician Protection Act” in weekly speeches. The House Republican leader, Representative Kevin McCarthy of California, produced his own video to define the bill.

“This is a terrible proposal,” Mr. McConnell said on Wednesday. “This is a solution in search of a problem. What it really is is a bill designed to make it more likely that Democrats win more often.”

Democrats are standing by their legislative handiwork. Now they have to sell it.

“It’s going to become, I believe, a marker of what the Democratic brand is,” Representative John Sarbanes, Democrat of Maryland and the lead sponsor of the legislation, said in an interview. “We stand for reform, we stand for democracy, we stand for cleaning up our politics.”

So what is in H.R. 1?

Campaign finance transparency

Some of the most debated provisions are intended to disclose who is paying for online political ads and financing so-called dark-money groups. The Disclose Act, part of the bill, would require super PACs and nonprofit organizations that spend money in elections to disclose the names of donors who contribute more than $10,000. Democrats say such disclosure is broadly popular with voters in both parties.

“Congress cannot meaningfully address the nation’s significant challenges without first recognizing and acknowledging the undue influence of special interests in our politics,” said Representative Abigail Spanberger, Democrat of Virginia.

Some of those provisions, however, have drawn criticism from both conservative and liberal groups that argue the language is overly broad and would infringe on First Amendment rights.

Representative Steve Scalise of Louisiana, the minority whip, said the legislation would turn the Federal Election Commission “into a ‘speech czar’ with the power to enforce Democrats’ vague definition of ‘campaign-related speech.’” The American Civil Liberties Union has urged members to oppose the legislation.

“Communications that refer to a candidate in the context of an important public policy issue may have nothing to do with supporting or opposing that candidate’s election, and yet that speech would trigger disclosure,” the organization said in a 13-page letter laying out its concerns.

The legislation would establish a six-to-one matching system for donations of up to $200 to congressional and presidential candidates who reject high-dollar contributions. That system would be funded by an additional fine on corporations found to have broken the law. Republicans call that welfare for politicians.

“Make no bones about it: No matter how they try to move a shell game around, the cost will be borne as another mandatory spending program in Washington,” said Representative Rodney Davis of Illinois, the ranking Republican on the House Administration Committee.

Eliminating barriers to voting

The legislation seeks to make it easier to vote. It would designate Election Day as a federal employment holiday and automatically register citizens to vote, restore voting rights to those who have served felony sentences and encourage same-day voter registration.

It also would prohibit voter-roll purges, a technique employed by states to prune outdated registrations but one that voting rights advocates say has been used to disenfranchise eligible voters, especially minorities. Such purges have been subjected to court challenges in Ohio and Texas.

“Voting is crucial, and I don’t give a damn how you think about it,” Representative Elijah E. Cummings of Maryland, the chairman of the House Oversight and Reform Committee, said in a fiery hearing on the legislation. “I want to be clear: that when they look back on this moment 200 years from now, there are those of us who stood up and said, ‘We will defend the right to vote.’”

Republicans have expressed concern about allowing felons to vote, although in most states, felons can regain their voting rights after they are released (as in Massachusetts and Hawaii), after they complete their parole (as in Colorado and Connecticut) or when they are no longer on parole or probation (as in New Jersey and Texas).

“Not only is this dangerous, it’s unconstitutional,” Mr. McCarthy said in his video attacking the legislation.

Mr. McConnell threw cold water on the proposal to make Election Day a federal holiday.

“What affects turnout more than anything else is interest and competition,” he said. “We got a lot of federal holidays in America. I personally don’t see any point in having more.”

Holding the president and other officials accountable

The legislation also provides House Democrats with another opportunity to jab at President Trump with a series of ethics-law changes that cut to the heart of some of the controversies bedeviling Mr. Trump.

It would require presidents and vice presidents, as well as candidates for the nation’s highest offices, to release at least 10 years of federal tax returns — Mr. Trump has released none — and it stipulates that inaugural committees must disclose their expenditures. Mr. Trump’s inaugural committee, which raised a record $107 million and spent lavishly, is being investigated by prosecutors in New York.

Asked whether he would support the measure that requires presidential candidates to disclose tax returns, Mr. McConnell remained impassive: “We’ll be happy to look at it.”