Ever since Bernie Sanders, the independent senator from Vermont, announced that he would seek the Democratic nomination for president, he has drawn comparisons to a similarly disheveled, longtime politician with a cult-like following and a strong independent streak: former Congressman Ron Paul, who ran for the Republican nomination in 2008 and 2012. It’s true that Sanders and Paul have a lot in common: They both have rabid fan bases, don’t hold their tongues, and embrace ideologies that are rejected by the establishment of their respective parties. And like Paul, Sanders could challenge his party’s frontrunner early on, but doesn't stand much of a chance of winning the nomination. As Slate’s Jamelle Bouie wrote this week:

Sanders won’t be the Democratic nominee. But that doesn’t mean he won’t be important. Here, it’s useful to think of Ron Paul … He helped bridge the divide between libertarians and the Republican right, and he inspired a new group of conservative and libertarian activists who have made a mark in the GOP through Paul’s son, Kentucky Sen. Rand Paul. If Sanders can sustain and capture the left-wing enthusiasm for his campaign, he could do the same for progressives.

I disagree; Sanders’s campaign isn’t simply one that will put “democratic socialist” ideas on stage against a more mainstream Democratic view, as Paul sought to do with his libertarian ideas. Rather, his candidacy represents a wing of the Democratic Party whose influence on the establishment is increasing with each election, as moderate Democrats (and their Republican counterparts) become extinct

For a more apt Republican analog to Sanders' campaign, one must go back to 2000. John McCain, like Sanders, was thought to have little chance to defeat George W. Bush, who, as the son of a former president and governor of a major electoral state, had more money and more party support. But McCain harnessed the anti-establishment sentiment of the time to build a strong online following, at a time when the internet’s infancy as a political tool. He fought a hard campaign against Bush, even winning the New Hampshire primary, before being knocked out of the race in early March.

Apart from the major issue of campaign finance reform, however, he had very little major policy or ideological differences with Bush and the Republican establishment. What set him apart was his press-appointed “maverick” status: He was willing to say things in public that no other candidate would—what David Foster Wallace, in his classic profile of the McCain campaign, called “obvious truths that everyone knows but no recent politician anywhere’s had the stones to say.” (His campaign bus was even called the “Straight Talk Express.”)

Likewise, Sanders refuses to hold his tongue. In June, he opened an interview with HBO’s Bill Maher by saying, “This campaign is about a radical idea: we’re going to tell the truth.” And that message seems to be working with liberals and even disaffected voters. As one New Hampshire resident, a self-described undecided independent voter, told The New Republic recently, “Do I think he can win? No. But I do like the somewhat fresh take of being a straight shooter.”

And much like Bush and McCain fifteen years ago, Clinton and Sanders are closer on the issues than a lot of progressives would like to admit. Sanders is championing reforms—a legislative or constitutional fix to Citizens United, universal healthcare, increased regulation of the financial system, income inequality—that most Democrats have supported for years, including Clinton; she was the face of the universal healthcare fight during Bill Clinton’s first term and has focused on income inequality and Citizens United in her 2016 campaign. Similarly, McCain’s biggest issues in that 2000 campaign—national defense and the Middle East—would define the Bush administration and the neoconservative movement as a whole for the next decade.

On the major issues that Sanders and Clinton disagree on—the extent to which the banking system should be reformed, surveillance, and free trade—Sanders’s position is just as popular within the party as Clinton’s, if not more so. These are the battles for the future of the Democratic Party, and where both Sanders and Clinton will seek to stake out a position independent of the other. And in those few instances where McCain and Bush disagreed, like the McCain-led campaign reform act, a McCain bill that expanded rights for terrorism detainees, and how much of a role social conservatism should play in the Republican Party, the disagreements were public. 

McCain’s challenge to Bush was ultimately unsuccessful, but both were neoconservatives working toward the same goal. McCain campaigned for Bush, voted with the administration's position 95 percent of the time, and was an ardent supporter of the war in Iraq. Although we can’t possibly know how often Sanders would vote with a hypothetical Clinton administration, we do know they voted together during their two years spent as Senate colleagues 93 percent of the time. And given Sanders’s endorsement of Obama in 2008 and 2012, it’s likely that, should he lose, he would throw his weight behind Clinton. John McCain may not have liked Bush much, but he supported him in both 2000 and 2004. In 2008, Ron Paul snubbed both McCain and the Libertarian Party candidate, instead endorsing the Constitution Party candidate, and refused to "fully support" Mitt Romney in 2012. 

Similar to 2000, a dark-horse candidate running a candid campaign in has emerged as the principal challenger to the frontrunner, one he’s a long shot to defeat. And like that first McCain bid for the presidency, Sanders's loss would be because Clinton is a strong nominee who is more well-known and deemed an acceptable general election candidate to a majority of Democrats—not because his ideas are too fringe, as Paul's were in his campaigns, for his party’s base.

Correction: An earlier version of this article stated that Ron Paul "only begrudgingly supported Mitt Romney in 2012." Paul said at the time, "I don’t fully endorse him for president."