Trump, Sanders gaining ground in NH
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Republican front-runner Donald TrumpDonald John TrumpTrump and Kim fight PR war as summit talks collapse Trump appears to confirm deal on Chinese firm ZTE Judge rejects Manafort's attempt to throw out some charges MORE and Democratic presidential candidate Bernie SandersBernard (Bernie) SandersTrump: ‘Clapper has now admitted there was spying on my campaign’ Overnight Defense: Trump decision on Korea summit coming 'next week' | China disinvited from major naval exercise | Senate sends VA reform bill to Trump Senate sends major VA reform bill to Trump's desk MORE are seeing increased support atop their parties' respective fields in New Hampshire, according to a new Franklin Pierce University-Boston Herald poll.

Trump holds a 25-point lead over his closest rival, Ted CruzRafael (Ted) Edward CruzGOP senators introduce Trump's plan to claw back billion in spending Pro-Trump super PAC raises .5 million in 6 weeks Trump has exposed Democratic hypocrisy on prison reform MORE, according to Sunday's poll. He has 38 percent of support among likely GOP primary voters, with Cruz taking only 13 percent. Former Florida Gov. Jeb Bush and Florida Sen. Marco RubioMarco Antonio RubioTrump appears to confirm deal on Chinese firm ZTE Hillicon Valley: Experts worry North Korea will retaliate with hacks over summit | FBI works to disrupt Russian botnet | Trump officials look to quell anger over ZTE | Obama makes case for tighter regs on tech Putting pressure on Trump, House passes bill barring government from doing business with ZTE MORE follow with 10 percent. Ohio Gov. John Kasich comes in fifth place with 8 percent. 

Trump had 33 percent support in a similar poll a week ago.

But 44 percent of Republican primary voters said in the poll they could still change their minds about their choice of candidate. Still, 57 percent of Republican primary voters in New Hampshire believe Trump will be the nominee, according to the poll.

In the Democratic race, Sanders hold a 20-point lead over Hillary ClintonHillary Diane Rodham ClintonTrump lashes out at 'rigged' Russia probe in pair of tweets Clapper: 'More and more' of Steele dossier proving to be true Republicans are strongly positioned to win Congress in November MORE among likely Granite State primary voters, according to the poll. Sanders has 57 percent support over Clinton's 37 percent. Sanders's support is is 2 points higher than last week's poll.

About 78 percent of likely primary voters said they won't be changing their minds about their decision.

The polls, conducted between Jan. 26-30, have a 4.7 percent margin of error for Republicans and 4.9 percent margi of error for Democrats.

Sanders and Trump also hold large leads in the RealClearPolitics average of polls in New Hampshire. Trump has an 18.2 point lead, with 31.4 percent support, over John Kasich, who has only 13.2 percent. Sanders holds a 14.3 point lead over Clinton in the RealClearPolitics average, taking 53.7 percent of the vote compared to Clinton who only has 39.4 percent.