Election law attorney Marc Elias is cheering Democrats' voting and campaign finance reform legislation while seeking to overturn the certification of an Iowa election.

"No matter how late it gets tonight, this is urgent!" Elias tweeted Wednesday of the For the People Act of 2021, known as H.R. 1, which passed in the House by a vote of 220 to 210.

At the same time, Elias is helping to challenge Iowa Republican Rep. Mariannette Miller-Meeks' 2020 election win. In January, Meeks was finally sworn in after the election was certified by six votes over former Democratic Iowa state Sen. Rita Hart.

A House committee charged with investigating the matter officially met for the first time on Feb. 10 to discuss the matter. 

(Mariannette Miller-Meeks (Miller-Meeks campaign))

"Six votes separate the two candidates. We have identified 22 ballots for Hart that were wrongfully rejected. Now it looks like Miller-Meeks is scrambling," Elias tweeted on Feb. 8.

HOUSE CANCELS THURSDAY VOTES AMID SECURITY THREATS AT CAPITOL

A number of the 22 rejected ballots Elias identified were invalid due to registration and absentee voting issues, according to the Quad-City Times.

H.R. 1 would enact automatic voter registration, expand early voting access and absentee voting, restore voting rights to felons after they have completed their sentences, prohibit voter roll purges and partisan gerrymandering, impose new campaign finance rules, require presidential nominees to release 10 years of tax returns and take aim at big-dollar donors and dark money.

IOWA CONGRESSIONAL CONTEST HEATS UP AS HOUSE TAKES FIRST STEP TO CONSIDER ELECTION CHALLENGE

Elias did not immediately respond to an inquiry from Fox News asking if H.R. 1 would potentially lead to more legal election challenges like the one he is leading for Hart.

Former Iowa State Sen. Rita Hart speaks with a reporter at her farm in Wheatland, Iowa, on Tuesday, Aug. 13, 2019. (Caroline Brehman/CQ Roll Call) 

Another major pillar of the legislation would establish a new public financing system for congressional and presidential elections to incentivize small-dollar donations. The legislation would establish a 6:1 match for each grassroots contribution to a candidate up to $200.

No Republicans joined with Democrats in approving the sweeping voter rights reform that now heads to the Senate, and 20 Republican state attorneys general are calling the bill "unconstitutional."

BIDEN CELEBRATES HOUSE PASSAGE OF H.R. 1, DEMS' CAMPAIGN BILL, VOWS WORK TO 'REFINE AND ADVANCE' LEGISLATION

President Biden applauded House Speaker Nancy Pelosi and House Democrats for passing H.R. 1 "in the wake of an unprecedented assault on our democracy; a coordinated attempt to ignore, undermine, and undo the will of the American people never before seen in our history; and a new wave of aggressive attacks on voting rights taking place in states across the country."

CLICK HERE TO GET THE FOX NEWS APP

"The right to vote is sacred and fundamental — it is the right from which all of our other rights as Americans spring. This landmark legislation is urgently needed to protect that right, to safeguard the integrity of our elections, and to repair and strengthen our democracy," he said, adding that he looks forward to "signing it into law after it has passed through the legislative process."

Fox News' Marisa Schultz contributed to this report.