The bipartisan effort to prevent future attempts to overturn a presidential election during the ceremonial counting of Electoral College votes hit a speed bump Wednesday, though passage before the end of the current Congress still looks likely.

Senators Susan Collins, R-Maine, and Joe Manchin, D-W.Va., produced a draft bill in July to correct the shortcomings in the 1887 Electoral Count Act exploited by former President Donald Trump in his effort on Jan. 6, 2021 to remain in power despite losing the 2020 election. That bill had earned the support of 11 Republicans as of Thursday morning – one more than the magic number needed to overcome a filibuster in the evenly divided Senate – after Sen. Pat Toomey of Pennsylvania announced he would co-sponsor it.

But on Wednesday, leaders of the Democrat-controlled House passed over a bill with language matching the Senate legislation in favor of a slightly tougher bill co-sponsored by Rep. Liz Cheney, R-Wy., and Rep. Zoe Lofgren, D-Calif. The move, which came as a surprise to many senators, means the two bills would need to be reconciled without losing more than two of the current Senate Republican supporters.

The Senate bill closes the door on anyone repeating Trump’s attempt to pressure a Vice President to arbitrarily block ceremonial certification of the final Electoral College ballots by explicitly stating that vice presidents don’t have the power to judge or overturn the electoral college results. It also raises the bar for lodging objections to Electoral College results from one member of Congress to at least one-fifth of the members, and eliminates a loophole that state Legislatures could use to throw out election results simply by declaring the election to be “failed.” These changes received broad support from an ideologically mixed panel of election experts at a hearing before the Senate rules committee Aug. 3.

The House version, which passed 229-203 with nine Republicans in favor, sets the bar even higher for lodging objections to the results, at one third of members instead of one fifth.

Sen. Collins did not respond to a question about how the House bill’s differences might affect Republican support and Senate passage. But on Monday, when the Cheney-Lofgren bill was introduced, she told the Washington Post: “I much prefer our bill, which is the product of months of study, input from constitutional and election experts, and is a bill that has garnered widespread bipartisan support.”

“I believe that we can work this out,” Collins added, “and I hope that we both do so.”

All House Democrats voted for the Cheney-Lofgren bill including both of Maine’s House members, Chellie Pingree, D-1st District, and Jared Golden, D-2nd District.

Rep. Pingree did not respond to an invitation to discuss the relative merits of passing the slightly tougher bill instead of a measure introduced a week ago by Michigan Republican Fred Upton and New Jersey Democrat Josh Gottheimer that was essentially identical to the Senate one, presumably removing any potential obstacles to quick passage.

Instead, her spokesperson shared a written statement on her support for the Cheney-Lofgren bill. “We will not stand by and let the dangerous lies and rhetoric of Donald Trump and his loyalists threaten the electoral process ever again,” Pingree wrote, referring to the storming of the Capitol on Jan.6. “I’m proud to join my colleagues on both sides of the aisle in passing this crucial legislation to protect and strengthen our democracy.”

Collins and Manchin issued a statement Thursday celebrating Sen. Toomey having joined the list of Republican co-sponsors of the Senate bill.

“We are delighted that bipartisan support continues to grow for the Senate’s sensible and much-needed reforms to the Electoral Count Act of 1887,” the senators said. “Our bill is backed by election law experts and organizations across the ideological spectrum. We will keep working to increase bipartisan support for our legislation that would correct the flaws in this archaic and ambiguous law.”

Sen. Angus King, a Maine independent who caucuses with Democrats and helped draft a set of Electoral Count Act reform recommendations used by the bipartisan group, also supports the measure. Last week he told the Press Herald it was vital that the bill be passed. “We learned on January 6^th that if we have a law that is ambiguous or confusing it leads to potential abuse,” he said.

While the Electoral Count Act reforms have some bipartisan support, many Republicans have balked at proposals to protect other aspects of elections, including measures to make it easier for people to register and vote nationwide that have long been standard practice in Maine – same-day voter registration, early in-person voting, and mail-in absentee ballots – as well as requiring electronic voting machines to have paper trails as a remedy to suspected hacking.