Hillary Clinton, still struggling to fend off the primary challenge from Bernie Sanders, deployed her “secret weapon” this week: her husband, Bill, who delivered his first campaign speech on her behalf in Nashua and Exeter, N.H.

One can understand why. Unlike Hillary herself, Bill Clinton remains one of the most popular political figures in the country. His approval ratings consistently exceed 60 percent according to most polls.

Sure, there are blemishes. As Donald Trump didn’t hesitate to remind us, Bill Clinton’s sexual history is, shall we say, dubious. But viewed through the wreckage of the Obama and Bush presidencies, the Clinton era looks pretty darn good by comparison.

Indeed, Clinton spent much of his New Hampshire speech, not touting Hillary’s virtues, but reminding voters of his own presidential successes. At one point he went over two minutes without mentioning her name. But unfortunately for nostalgic voters, a Hillary Clinton presidency would be very different from Bill’s.

Bill Clinton, after all, was a “New Democrat,” the president who declared that “the era of big government is over.” Hillary is an unapologetic defender of ever bigger government. In that same State of the Union address where he announced the demise of big government, Bill went on to say that he had “worked to give the American people a smaller, less bureaucratic Government in Washington. And we have to give the American people one that lives within its means.” If Hillary said anything even close to that, her head would explode.

For example, Bill was a champion of free trade, pushing through NAFTA among other trade agreements. But Hillary is campaigning as a protectionist, even repudiating the Trans-Pacific Partnership that she helped negotiate.

Bill — pushed, of course, by Republicans in Congress — brought us welfare reform. Hillary seeks to expand the American welfare state.

Bill presided over the first and only balanced budgets since the Nixon administration. Federal spending averaged just 19.2 percent of GDP during the Clinton presidency and bottomed out at just 17.6 percent, the lowest level since 1966. Hillary Clinton, on the other hand, has already called for more than $1.1 trillion in new spending over the next ten years. And while Bill seriously explored entitlement reform, even considering the possibility of allowing younger workers to invest privately a small portion of their Social Security taxes, Hillary not only opposes any efforts to “cut or privatize the program,” she actually wants to expand it to offer new and additional benefits.

Bill Clinton’s presidency was hardly a golden age of small government. But there were notable successes on the deregulation front, including in telecommunications, transportation, and financial services. Today, Hillary proposes a host of new business regulations — a higher minimum wage, paid family and medical leave, and fixed rather than flexible schedules. She believes that Dodd–Frank doesn’t go far enough. And she supports much tougher EPA regulations.

The media often bemoan the GOP’s move to the right. And it is true that the Republican party is, in fundamental ways, more conservative than it ever has been. But these same observers ignore the Democratic party’s move even farther to the left. The Democratic Leadership Council has been supplanted by Occupy Wall Street.

Some wonder whether Ronald Reagan would be labeled a RINO by today’s Republicans. Perhaps. But there is no doubt that Bill Clinton would never be nominated by today’s Democratic party.

In fact, it is doubtful that today’s Democratic party would even nominate the Hillary Clinton of 1992–2000. She has had to “evolve” on a host of other issues besides the ones mentioned above — same-sex marriage, the Iraq war, and even undocumented immigrants. Certainly, no one can accuse her of “a foolish consistency,” to borrow Emerson’s phrase.

At the start of his New Hampshire speech, Bill Clinton remarked that, when it comes to politics today, “I don’t fit anymore.” He was referring to the voter anger driving the Trump candidacy, among other things. But he might just as well have been talking about today’s Democratic party or his wife’s campaign.

Michael Tanner is a senior fellow at the Cato Institute and the author of “Going for Broke: Deficits, Debt, and the Entitlement Crisis.” Send comments to [email protected].