A billionaire turned political activist is visiting New Hampshire to try to build support for impeaching President Donald Trump.Tom Steyer said the future of the country depends on the success of his controversial mission. Steyer made a fortune managing a hedge fund, and over the past decade, he has been using his financial resources to try to shape the nation's politics through his organization, NextGen America. Since the fall, Steyer has been arguing that Congress needs to impeach Trump. "And it's been much more successful than any would have expected," Steyer said. "We have almost 5.5 million people who've signed our petition drive." Steyer said he believes grounds for impeachment exist in the emoluments clause of the Constitution, which prevents the president from accepting payments or gifts from foreign officials. Steyer contends that foreign money is flowing to the president through his global real estate holdings. Steyer also pointed to the investigation into Russian meddling in the U.S. election, and he said the case against Trump has only gotten stronger over time. "The president continues to break the law," Steyer said. "He continues to act in contradiction to the interests of the American people. He continues to threaten the democracy." A successful impeachment effort would elevate Vice President Mike Pence to the presidency. In an interview with WMUR's "CloseUp," Steyer said President Pence would be a major improvement. "That would be a gigantic step forward in terms of preserving the democracy, protecting the American people and making a statement to ourselves and the world about what our basic values are," he said. Steyer's campaign has been criticized by some elected Democrats, while Republicans have been more universally dismissive. New Hampshire Republican Party Chairman Wayne MacDonald slammed Steyer's visit. "Any talk of impeachment is just ludicrous," MacDonald said. "Democrats need to get over their 2016 election loss and move on."