What’s a signed political pledge worth?  

With all three remaining Republican presidential candidates backing away from the promises they made to the Republican National Committee to support the party’s White House nominee, other loyalty oaths may similarly fall out of favor.  

Real estate mogul Donald Trump, Texas Sen. Ted Cruz and Ohio Gov.  John Kasich all told a CNN town hall Tuesday that they may not stick to their signed RNC pledges. “All of us shouldn’t even have answered that question,” Kasich told CNN of the Republican Party’s pledge.  

The pledge also required candidates to vow not to run as an independent or another party’s candidate for the presidency. It’s hardly the only attestation the White House contenders have encountered on the campaign trail.  

Lobbying groups of all kinds are pursuing more pledges as a way to get candidates on the record and make promises while voters are paying attention.  

Candidates for Congress and the White House this cycle can take a pledge to reject political money from fossil fuel interests. Presidential hopefuls have been asked to close the revolving door between Wall Street and the federal government in their executive branch appointments. And they can always embrace the decades-old pledge that they will not support a tax increase while in office.  

But how much power is there in a political pledge, especially if Republican presidential contenders are already breaking one to the GOP itself? If lawmakers and presidents disavow their promises once in office, such pledges aren’t worth the paper they’re written on.  

Even if they keep their word, there can be a downside as Trump, Cruz and Kasich now contend.  

“There are hundreds of pledges that are submitted to campaigns, and it puts the candidate in a box,” said Ryan Williams, a senior vice president at FP1 Strategies who worked on Mitt Romney’s 2008 and 2012 presidential campaigns. “These pledges are an attempt by a lot of groups to wield political clout and hold candidates to their standards, but many of these pledges are very black and white — sometimes candidates like to find gray area.”  

The prevalence of political pledges, Williams noted, may be why some lawmakers are unwilling to compromise.  

Cruz, in backing away from the RNC pledge, explained that circumstances had shifted with increasingly nasty rhetoric involving candidates’ personal lives. “I’m not in the habit of supporting someone who attacks my wife and my family,” Cruz told the CNN town hall.  

To have any staying power, a pledge must ultimately be enforced by voters — not by the lobbying groups or parties that craft them, said Grover Norquist, author of the Taxpayer Protection Pledge, one of the best known.  

In that one-sentence pledge, candidates vow to the American people that they will “oppose any and all efforts to increase the marginal income tax rate for individuals and/or businesses.”  

Nearly all sitting Republican lawmakers and GOP congressional candidates have signed the tax pledge. Norquist said he has secured signed copies from all the remaining Republican presidential hopefuls except front-runner Donald Trump.  

Trump’s people say the pledge document is on the way, Norquist said.
“One reason why the Taxpayer Protection Pledge is often mimicked, but rarely successfully, is that the pledge is one thing and it doesn’t change,” said Norquist, president of Americans for Tax Reform, who launched the pledge in 1986.  

Sticking to the tax pledge is totally within the signer’s control. It’s not a promise to repeal, for example, the 2010 health care law, which would  require a cooperative effort to accomplish.  

Though most voters, especially this cycle, would likely roll their eyes when asked if politicians really keep their promises, academic research has found that at least with the taxpayer pledge, lawmakers take it very seriously.  

That pledge “is quite effective at locking politicians into anti-tax positions,” wrote Stanford University’s Michael Tomz and Robert P. Van Houweling of the University of California, Berkeley, in a 2012 paper titled “Political Pledges as Credible Commitments.”  

Even amid periods of national crisis, such as the debt-ceiling debate of 2011, Republicans held the line against any deals that would have included tax increases, the academics concluded.  

“Written campaign pledges hold up better than verbal ones because putting it down on paper or on a website makes it more concrete in the eyes of candidates and interest groups,” said Darrell West, director of governance studies at the Brookings Institution.  

It’s that kind of policy muscle that many organizations are seeking with new pledges this year.  

But if the RNC pledge is any indication, candidates may increasingly be willing to tear up such promises.  

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