On the day he became Utah’s senior senator, Republican Mike Lee turned to Facebook to urge Gov. Gary Herbert to abandon his support of SB54, the state’s dual-track election law that allows candidates to reach a party’s primary election by gathering signatures.

“Gov. Herbert, you’re a good man and a hardworking public servant,” Lee wrote. “For the love of the Constitution — and for the good of all political parties — please stop defending SB54. It’s unconstitutional.”

The post generated more than 100 comments, including some from the bill’s Utah House sponsor, now-Sen. Dan McCay, R-Riverton. McCay wrote that he sees clearly now that SB54 was a mistake, and that he hopes the U.S. Supreme Court will strike it down.

“In full candor, there isn’t a night that SB54 isn’t the last thing on my mind before I go to sleep," McCay wrote. “The ‘woulda, coulda, shoulda’s’ haunt me and that’s probably appropriate.”

On Friday, McCay told The Tribune he plans to sponsor legislation during the upcoming session to repeal SB54. Various attempts have been made by individual lawmakers to repeal the controversial law — which was originally conceived as a compromise to avoid a ballot initiative — but so far none have earned the support of both Utah legislative chambers.

“I want to make sure we have options during the session on election law,” McCay said.

Under SB54, partisan candidates have the option of qualifying for a primary ballot either by winning the support of party delegates at a caucus or convention, by gathering signatures, or both. The 2014 change, pushed by the group Count My Vote, has been increasingly used by Utah political candidates as a fail-safe to avoid being eliminated from contention by convention delegates — a relatively small group of partisans that tend to skew toward the ideological wings of each party.

The candidates who gathered signatures last year included Sen. Mitt Romney, R-Utah; Rep. John Curtis, R-Utah; and incoming Utah House Majority Leader Francis Gibson, R-Mapleton. And many other candidates declared their intent to gather signatures but either abandoned those plans, failed to submit their signatures, or fell short of the law’s signature thresholds, including Rep. Ben McAdams, D-Utah; incoming Senate President Stuart Adams, R-Layton; incoming Senate Majority Leader Evan Vickers, R-Cedar City; former Rep. Mia Love; and incoming House assistant majority whip Val Peterson, R-Orem.

And despite his opposition to the law, Lee opted to collect signatures during his most recent re-election campaign in 2016.

“SB54 was the law of the land at the time and Senator Lee was determined to follow the law,” said Conn Carroll, Lee’s spokesman.

But the law only creates the option of collecting signatures, going through the convention process, or both, meaning a candidate is free to choose his or her route to the party nomination. When asked if Sen. Lee believed he was compelled to collect signatures, Carroll responded “nope.”

Carroll later added that Lee has nothing against the signature process.

“He does believe that parties ought to have the ability to choose how they choose their own candidates through,” Carroll said, “and he looks forward to the courts resolving the issue."

Lee was first elected in 2010, ousting popular three-term Sen. Bob Bennett in the Republican Convention by riding a tea-party wave at the time. Many supporters of SB54 have pointed to the Bennett defeat and that of former Gov. Olene Walker as a reason for the signature-gathering option to get around convention delegates that don’t reflect the views of mainstream voters.

The Utah Republican Party has engaged in a yearslong and costly effort to challenge the dual-track election law in court, with a federal judge in Utah and the 10th Circuit Court of Appeals rejecting the party’s claims that SB54 is unconstitutional. The party has submitted an appeal to the United States Supreme Court, which has not yet determined whether to hear the case. But last month, justices asked the state of Utah to respond to the Utah Republican Party’s appeal.

Responding to comments on his Facebook post, Lee wrote that he hopes the court will take up the case and would expect the law to be struck down. But he added that a review by the Supreme Court is not guaranteed.

“My point is simply that we shouldn’t take any chances,” Lee wrote. “The legislature and governor should repeal this unconstitutional law.”

Paul Edwards, spokesman for Gov. Herbert, declined to comment.

Herbert has repeatedly bemoaned the continued legal challenges of SB54 from the party’s right wing, saying it only serves to divide the GOP.

McCay said the increasing number of lawmakers taking advantage of the signature-gathering route doesn’t necessarily undermine a potential repeal effort in the state Legislature, since most candidates continue to participate in party conventions.

“There are a few exceptions,” McCay said. “For the most part, everyone is still going through the caucus-convention process.”

While most of the comments on Lee’s post were sympathetic to his opposition of SB54, some questioned the purpose of a U.S. senator communicating with the state’s governor through social media.

Paul Mero, president of Next Generation Freedom Fund and former president of the conservative Sutherland Institute, wrote that the question of SB54′s constitutionality should be settled by the courts. But Lee’s post, Mero said, was “stirring up the crazies” who have made support or opposition to SB54 a litmus test.

“You’re a student of constitutional law ... these crazies are not,” Mero wrote to Lee. “You understand context. They do not. This public plea to the governor makes little sense.”