It’s been 22 years since the last amendment to the Constitution took effect, but Senate Democrats are hoping to alter the nation’s founding document once again.

The likelihood of crossing the threshold to amend the Constitution over campaign finance is slim to none, however. An amendment would have to garner support from two-thirds of the House and Senate, before being approved by three-fourths of the states.

Despite that seemingly insurmountable hurdle, Senate Democrats are forging ahead with a plan to bring S J Res 19 to the floor.

This resolution would add a 28th Amendment, stating that Congress can regulate contributions and spending in federal elections. It would also give state governments the same authority in statewide contests.

Democratic leaders have already said they plan to bring the amendment up for a vote in the Senate by the end of the year. But the resolution’s sponsor, Sen. Tom Udall, D-N.M., is hoping for a vote before the midterm elections.

“I’m going to be pushing for a vote before November,” Udall told CQ Roll Call.

This amendment “has no chance whatsoever of being adopted,” said Rick Hasen, a law professor at the University of California, Irvine. “I think it’s more a matter of keeping the issue in the public eye and scoring political points than it is about actually changing the Constitution.”

Despite the unlikelihood of passage, the push has Republicans crying foul.

“This is an election year effort to try to silence people who our Democratic colleagues don’t agree with,” Senate Minority Whip John Cornyn, R-Texas, said.

Cornyn called the amendment “an outrage” and his fellow Judiciary Committee Republicans echoed his argument that Udall’s proposal limiting political spending also limits free speech.

“Putting Congress in charge of who gets free speech is about the worst idea I’ve heard in a long, long time,” Sen. Jeff Flake, R-Ariz., said. “So let them bring it to the floor.”

Before a vote in the chamber, the resolution will have to pass the Judiciary Committee. Udall’s amendment is likely to advance out of committee even if all of the committee’s Republicans vote “no” because, aside from Chairman Patrick J. Leahy, D-Vt., all of the committee’s Democrats are co-sponsors of the resolution.

“It would probably be out [of committee] within a month, month and a half,” Udall predicted.

Udall and his fellow Democrats said now is the time to address money in politics, despite Republican opposition and the high threshold for passage.

“All of this outside money and the inability of us to put any limits on it is a scourge on our elections and our democracy no matter what side you’re on,” Sen. Amy Klobuchar said.

Klobuchar’s fellow Minnesota Democrat, Judiciary Committee member Al Franken, also argued that placing limits on campaign contributions does not violate the right to free speech.

“It simply restores the First Amendment to the meaning it had for decades before the Supreme Court twisted it into a blank check for deep-pocketed corporations and special interest groups to spend unlimited money on elections,” Franken said.

Recent Supreme Court rulings about the legality of campaign finance laws have prompted activists to turn toward amending the Constitution.

Even Sen. John McCain, R-Ariz., a long-time proponent of campaign finance limits who disagrees with Udall’s proposal, said that amending the Constitution is the next necessary step for an effective campaign finance overhaul.

“I think you’re going to have to do a constitutional amendment because of the Supreme Court’s decision,” McCain told CQ Roll Call.

The amendment strategy posits that in order to change how the courts judge campaign finance laws, the basis on which they judge the laws must be changed.

Since the 1976 Supreme Court ruling in Buckley vs. Valeo, courts have judged campaign finance laws in the context of whether they violate the right to free speech.

Should Udall’s amendment be adopted, “The courts would have to interpret the Constitution in light not only of the First Amendment but also of the new amendment,” Hasen said.

In other words, this amendment would weaken the case that campaign finance laws violate the First Amendment because the court would be able to point to the new amendment as justification for stricter regulations.

This strategy of changing the Constitution to address campaign finance has been part of an expanding national grass-roots movement. That campaign emerged as part of the backlash to the Supreme Court’s Citizen’s United vs. Federal Election Commission decision, which ruled that the government cannot limit corporate spending in political campaigns.

Since Citizen’s United, 16 states have passed measures urging Congress to pass a constitutional amendment overturning the court’s decision. In Montana and Colorado, voters overwhelmingly supported a constitutional amendment in statewide ballot initiatives. Resolutions are also pending in 22 states.

“The movement is happening here in D.C. because there’s a movement out there that’s working through the state efforts,” said Marge Baker, vice president of policy and program for People for the American Way, a liberal advocacy group that is part of the grass-roots campaign.

According to United For the People, an online portal for the campaign’s groups, 123 organizations have pledged their support for amending the Constitution, including the NAACP, Greenpeace, and influential unions such as the SEIU and the UAW.

The movement is still fragmented by varying proposals for potential amendments. But the campaign could benefit as Udall’s amendment takes its place on the national stage when it comes to a vote in the Senate.

Rick Pildes, a constitutional law professor at New York University, said Udall’s proposal could bolster the movement by focusing the national debate and energizing its supporters.

“Even if passage is politically unrealistic,” Pildes said, “proposed amendments have historically served as important focal points for organizing and mobilizing the forces of political change.”

Although Udall’s amendment is not likely to be etched into the Constitution, it could have ramifications beyond the Beltway as a uniting force in the movement for a campaign finance overhaul.