If Mitt Romney wins the presidency, expect the Democrats to complain that the Republicans bought the election — and to try to outlaw it from ever happening again.

The signs are already emerging. A New York Times column earlier this month ran under the headline “Buying the Election?” The New Yorker magazine ran a long article by the editor of Thompson Reuters Digital, Chrystia Freeland, reporting, “the Republican National Committee and Romney…hold a huge cash advantage over Obama. The biggest shift has been among wealthy businesspeople, particularly in financial services. Romney’s advantage is compounded by the advent of Super PACs in this Presidential campaign, which are not subject to the same contribution limits as parties or candidates.”

“We’re already being outspent in key battleground states,” the Democratic Congressional Campaign Committee’s grassroots director, Angela Guzman, wrote in an email on August 30.

There’s a certain amount of hypocrisy about this charge. The same Times column that accuses Romney and the Republicans of buying the election observes that last time around, Barack Obama raised $750 million against Senator John McCain’s expenditure of about $84 million. I don’t recall a lot of Democrats the morning after the 2008 election complaining that Barack Obama or his donors had purchased the presidency.

To the contrary, when Democrats were on the buy side of these elections, they could laugh about it. At least, they used to be able to laugh about it. Senator John F. Kennedy went before the Gridiron Club in Washington on March 15, 1958 and announced, “I have just received the following wire from my generous daddy: 'Dear Jack—Don't buy a single vote more than is necessary—I'll be damned if I'm going to pay for a landslide.'"

Now that the Republicans are the ones doing the buying, though, the Democrats no longer see anything funny about it. Instead, they want to change the rules. Twenty-six senators—25 Democrats and independent socialist Bernie Sanders of Vermont—have signed on to Senate Joint Resolution 29, which would amend the Constitution to give Congress the power “to regulate the raising and spending of money and in kind equivalents with respect to Federal elections, including through setting limits on the amount of contributions to candidates for nomination for election to, or for election to, Federal office; and the amount of expenditures that may be made by, in support of, or in opposition to such candidates.”

President Obama has said, “I think we need to seriously consider mobilizing a constitutional amendment process to overturn Citizens United,” the 2010 Supreme Court ruling that struck down some of the campaign speech limits of the 2002 McCain-Feingold law. House Democratic leader Nancy Pelosi has said that if her party retakes a majority in the House of Representatives, she and her colleagues would approve such a constitutional amendment on their first day.

Earlier this month, New Jersey became the ninth state—after California, Connecticut, Maryland, Massachusetts, Hawaii, New Mexico, Rhode Island and Vermont—to back such a constitutional amendment by legislative vote, the Huffington Post reported.

Republicans, meanwhile, have their own worries about the election being bought. A recent column by the economist and CNBC journalist Lawrence Kudlow pointed to increased spending on food stamps and Medicaid and spoke of “Obama trying to buy the election with this entitlement explosion.”

There’s an important distinction to keep in mind, which is that the money supporting Romney is given voluntarily by people who own it and in many cases earned it, while the money spent on means-tested entitlements is money that is either borrowed from China or the Federal Reserve or taken in taxes. To be sure, not all recipients of means-tested entitlements will vote for the Democrats, just as not all million-dollar campaign donors will back the Republicans (ask Sam Walton, Steven Spielberg, or Jeffrey Katzenberg, who are giving to support Obama).

Elections actually turn out to be difficult to buy, as the many candidates who outspent their opponents but lost anyway—Meg Whitman is a good recent example—can attest. But if anyone wants to try, better they do it with their own money than with money taken in taxes using the force of law.

Democrats tempted to complain that the election was “bought” can always console themselves that the process reduces economic inequality by redistributing wealth from rich campaign donors to less-rich campaign consultants and owners of swing-state television stations. As for the proposal to amend the Constitution, a Democratic Party that heads in that direction is sending the message that it doesn’t expect to have another candidate with the financial advantage of John F. Kennedy in 1960 or Barack Obama in 2008 any time soon.