WASHINGTON -- Leading Democrats in Congress have all but given up on bringing in Republicans for their push to restore key provisions of the Voting Rights Act.

Marking the second anniversary of the U.S. Supreme Court's decision in Shelby County v. Holder, which removed the requirement that new voting laws be pre-cleared with the federal government in certain areas with a history of discrimination, a group of Democrats introduced an aggressive new bill Wednesday that would restore pre-clearance for states that include half the nation's population.

The senators and House members assembled Wednesday morning did not include any Republicans, after an effort to win bipartisan support in the previous Congress with a weaker bill fell flat.

Last year's bill would have put four states under pre-clearance at first, based on their violations over the past 15 years. The Voting Rights Advancement Act's pre-clearance formula would initially ensnare 13 states -- from Georgia to Florida to California to New York -- based on their number of voting rights violations over the past 25 years. States with a clean record over a period of time can graduate out of pre-clearance.

A Wednesday news conference was Democrats-only, a contrast with last year's bill that was co-written by Rep. Jim Sensenbrenner, R-Wis. The bill took some heat on the left for being narrowly defined and including an exemption for voter ID laws, but its backers said it was a vital compromise. Despite some warm talk from then-Majority Leader Eric Cantor, who soon went down in a primary, the bill never was seriously considered in the House.

Sen. Chris Coons, D-Del., bemoaned the fact that he could not get any Republican co-sponsors for the bill in Selma, Ala., this year, when 100 members of Congress joined to celebrate the 50th anniversary of Bloody Sunday.

Republicans in Georgia and elsewhere have argued that the other remaining tools in the Voting Rights Act, such as allowing lawsuits against discriminatory practices, are more than adequate to address problematic laws, and pre-clearance is too intrusive.

With both houses of Congress now controlled by Republicans, Democrats decided to go bold and fire up supporters in the 2016 election, rather than attempt an elusive compromise. As Selma native Rep. Terri Sewell, D-Ala., told reporters:

"For example ... tomorrow is the second anniversary of the Shelby decision. And so lots of civil rights groups – the NAACP, the National Action Network -- are going to have rallies around voting rights. And they're going to be talking about this bill. Because this bill is the one that's the most inclusive.

"And we just want to get our Republican colleagues to the table. I would be willing to compromise. That's how we do laws. But when they're not willing to talk at all, why not introduce a bill that is really more inclusive, more advanced, really does speak to inclusion? And that's what this bill does."

In addition to covering more states, the bill would beef up the federal government's ability to issue a preliminary injunction against a voting change, and it would establish a nationwide standard for swift review of practices that have been shown in the past to disproportionately affect minorities -- including voter ID laws.

In a prepared statement, Rep. John Lewis, D-Atlanta, said the renewed effort was necessary:

"If it was not clear in 2014, I think it is clear today that we have come a great distance in this country toward healing the divisions and problems among us, but we are not there yet. This legislation acknowledges that we still have much more work to do, but we have come too far, and we have made too much progress to stop now."

Sen. Dick Durbin, D-Ill., and others spoke of the recent massacre in Charleston, S.C., as a reminder of lingering racism. While praising movements in South Carolina and other states to remove the Confederate battle flag, Durbin said it's an ancillary issue:

"[That includes] the Voting Rights Act. This is fundamental. Make no mistake. Understand what this is about. This effort to stop the Voting Rights Act is a strategy to deny an opportunity to vote to many Americans, particularly to minorities."

The bill introduction was met with immediate praise from other Democrats and civil rights groups. But it stands little chance of whizzing through Congress.

Sensenbrenner, who led the 2006 reauthorization of the Voting Rights Act, said via a spokeswoman that he prefers last year's narrower bill:

"Restoring the VRA is critically important. Every American needs to know that we understand their right to vote is sacred. However, I stand by the legislation I introduced last Congress. Passing any bill on voting rights will be a Herculean task and there is no chance of succeeding if we abandon our bipartisan approach."