Bernie Sanders, the Vermont Senator and potential 2016 presidential candidate, will travel back to the early primary state of New Hampshire later this month, The Daily Beast has learned.

Sanders, the lone Socialist in the U.S Senate, will speak at a bookstore in the town of Warner, New Hampshire on June 28, on the subject of “rebuilding our economy and restoring our democracy.” That evening, he is slated to keynote a dinner celebrating grassroots activists arranged by the Hillsborough County Democratic Committee.

The trip comes as much of the political world will be dedicated over the course of the next week to Hillary Clinton’s book tour for her memoir about her time as Secretary of State. That tour, with its dedicated advance team, carefully stage-managed press availability, and multi-city itinerary, has all the hallmarks of a testing of the waters for a possible presidential run. And early polls give Clinton a gargantuan lead in a Democratic primary.

But Sanders has repeatedly criticized Clinton from the left, telling Time Magazine earlier this year that he would make a better president than her.

"I like Hillary… She’s a very, very intelligent person, no question about it," Sanders said then. "But I think, you know, if you talk about the need for a political revolution in America, I think it’s fair to say that Secretary Clinton probably will not be one of the more active people."

Although Sanders would face a steep challenge if he did run for president, he could give voice to the feeling of many in the Democratic Party who want the party to adopt a more aggressive, populist stance on Wall Street regulation, climate change, and economic growth. And such a candidate could suck up oxygen from Clinton as she tries to focus on the Republican Party, which will be hungry for the White House after eight years in the wilderness.

Sanders has called for a minimum wage above the $10.10 that Obama has proposed, further investment in the nation’s infrastructure, higher taxes on corporation and the wealth and a carbon tax.

“If [Clinton] does run, will she be as strong as the times require in taking on the billionaire class that has so much power? I’m not sure that she will be,” Sanders recently told The Washington Post. “Will she be as strong as needs be to address the crisis of climate change? I am not sure that she will be. Will she be as strong as needs be to take on the power of Wall Street? I’m not sure she will be.”

Sanders has made no decisions yet about running, but he has made all the moves that a possible candidate could make. The trip to New Hampshire will be his second to the early primary state in the last couple of months, and he also has visited the crucial early primary states of Iowa and South Carolina.