He also praised his Republican rivals, saying they are "terrific."
Sanders says what happened in New Hampshire will happen "all over this country."
"I want to say I still love New Hampshire, and I always will," she said.
Three candidates are fighting for third place in Tuesday's New Hampshire Republican primary after what looks like a resounding win for Donald Trump.
John Kasich broke away from the establishment pack to take second place...
RNC Chair Reince Priebus called New Hampshire a "crushing defeat" for Clinton.
The two senators have spent the past week in New Hampshire.
The Clinton campaign said it is already looking ahead to South Carolina and Nevada.
Denise Horn is coming onboard ahead of the crucial South Carolina primary.
This was a critical win for the billionaire to prove he can turn popularity into votes.
Just six months ago, she led in New Hampshire by 40 points.