DURHAM, N.H. — Hillary Clinton — campaigning at a college here and hoping Bernie Sanders can help deliver critical millennial voters — instead drew a crowd largely of baby boomers, while hearing faint praise from her former rival that paled in comparison to the language President Obama has used on the trail.

“There is no group of Americans who have more at stake in this election than young Americans, because so much of what will happen will affect your lives, your jobs, the kind of country we are, the kind of future we want to build together,” Clinton told a sea of gray hair and bald-spots at the University of New Hampshire campus field house yesterday.

The younger voters, among an audience of more than 1,000, were placed on risers on either side of the stage, highly visible spots that could be captured by TV cameras.

Sanders, who endorsed Clinton in July only to have the relationship stressed after hacked DNC emails revealed the scales may have been tipped against him, urged rallygoers to get out the vote.

“All of you know that New Hampshire is a battleground state,” the Vermont senator said. “All of you know that this is a very tight election. And, in fact, New Hampshire could decide the outcome. So I am asking you here today not only to vote for Secretary Clinton, but to work hard to get your uncles and your aunts, to get your friends to vote.”

He added it was “imperative” to elect Clinton.

Yet his comments were a far cry from the passionate rhetoric President Obama summoned to rally black voters earlier this month when he called it a “personal insult” to his legacy if they stayed home.

Clinton still leads Trump in most polls among youth voters, but not by the same large margins President Obama enjoyed in 2008 and 2012. She topped her GOP rival 48 to 23 among likely millennial voters in a poll by left-leaning NextGen Climate earlier this month, for instance.

In 2012, Obama clocked Mitt Romney among voters between the ages of 18 and 29 by a margin of 60-37 percent. In 2008, the gap was even larger, with Obama winning 66-32 percent over John McCain.

Libertarian Gary Johnson and Green Party candidate Jill Stein appear to be drawing many of the young Sanders holdouts.

“Bernie’s campaign energized so many young people,” Clinton acknowledged to the crowd.

She promised tuition-free public college for students with family incomes of $125,000 or less, a moratorium on debt payments for a few years after graduation, lower interest rates and loan forgiveness for students entering public service.

But on one condition, she added.

“None of this will happen if you don’t turn out to vote,” said Clinton. “None of it.”

Sanders, meanwhile, blasted Donald Trump for embracing tax breaks for the wealthy and trying to eliminate the estate tax.

Hundreds lined up hours ahead of time for the event, including many who drove more than two hours from parts of Massachusetts.

Earlier, Clinton received the endorsement of former Virginia U.S. Sen. John Warner, a Republican.

Meanwhile, Trump will hold a rally in Bedford, N.H., today.

Polls have shown Clinton leading Trump in the Granite State, though her advantages have ranged from 9 points to as low as 2.