Cruz drew explicit policy contrasts with Trump Monday. (REUTERS/Mark Kauzlarich (L) and Brian Snyder (R)/Files)

WHITEFIELD, N.H. -- Sen. Ted Cruz (R-Tex.) on Monday drew the most explicit policy contrasts between himself and Donald Trump to date, questioning his conservative credentials to voters here.

Over the past week, Cruz has eviscerated the odd political detante that existed between the two candidates. He punched back against Trump’s assertions that Cruz cannot run for president because he was born in Canada during a nationally televised debate Thursday. In the days after the Texas Republican has taken shots at the real estate mogul to the media. Monday night, he plainly laid out policy contrasts to voters for the first time and declared that he and Trump are in a battle for the nomination – by pivoting to Trump after being asked a question about the national debt.

“This race, nationally, is coming down more and more to a two-man race between me and Donald Trump,” Cruz said to a crowd in a high school in this town of 2,300 tucked in the White Mountains. The crowd started laughing.

“Who?” a man asked loudly.

Cruz managed to knock both Trump and Sen. Marco Rubio (R-Fla.) on immigration – an issue Cruz has praised Trump for bringing to the fore in the Republican primary. Cruz has long assailed Rubio for co-sponsoring a bipartisan bill that would have given undocumented immigrants a pathway to citizenship, something Cruz calls amnesty.

“When that fight was being fought Donald was nowhere to be found,” Cruz said.

“If you didn’t stand up and fight amnesty, when the stakes were live or die,” Cruz said, “I would suggest as voters you have reason to doubt the credibility of the promises of a political candidate who discovers the issue after he announces for president.”

Trump has said he wants to strengthen the nation's immigration system by building a wall with Mexico. He has made inflammatory comments about Mexican immigrants that led Macy's and Univision to sever ties with Trump. He has also called for a ban on Muslims coming into the United States.

Read: Donald Trump calls for ‘total’ ban on Muslims entering United States

The Texas Republican’s offensive is coming in New Hampshire, a state where Trump has a commanding lead in polls but Cruz is attempting to coalesce conservatives and siphon off libertarian-leaning voters.

Cruz questioned Trump’s outsider status, stating he has been part of the problem in Washington by supporting the bank bailout and President Obama’s economic stimulus package.

“On both of those, I opposed it. On both of those, Mr. Trump supported it,” Cruz said.

Cruz often talks about eminent domain here, especially in the state's more rural pockets, stating the government has no right to a person's property. Trump, Cruz said, supports eminent domain, making a veiled reference to Trump attempting to take the home of an Atlantic City, N.J., woman in order to build a casino.

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“Donald Trump has said he thinks eminent domain is fantastic, and he supports using government power to seize private people’s homes to give them to giant corporations to hypothetically build a casino,” Cruz said.

Despite stating Trump is “rattled” and “upset” at recent polls, Cruz insists that he will still “sing his praises” personally. Policy issues, however, are fair game.

In a campaign stop in Washington, N.H., earlier Monday, Cruz dismissed Trump’s assertion that his stances have changed – just like those of Ronald Reagan.

"Ronald Reagan did not spend the first 60 years of his life supporting Democratic politicians, advocating for big-government policies, supporting things like the TARP big bank bailout, supporting things like expanding Obamacare to turn it into socialized medicine. That’s not what Ronald Reagan did," Cruz told reporters.

Cruz: Trump is nothing like Reagan

He then rattled off a list of Democratic politicians to whom he said Trump donated money, including Chicago Mayor Rahm Emanuel, New York Gov. Andrew Cuomo and former representative Anthony Weiner. Cruz also said that Trump wants to maintain President Obama’s nuclear deal with Iran.

Jay McCusker, a 46-year-old mechanic from Dalton, N.H., said he is glad that Cruz is finally telling voters about how he and Trump differ, and is happy that the candidate said he doesn’t plan to make his attacks personal.

“That shows character,” he said.

McCusker said Trump “scares the hell out of me” and he wants Cruz to highlight the differences between the two more often to a national audience. McCusker said he wouldn’t vote if Trump is the Republican nominee.

“If Trump’s the nominee I won’t vote for him because I think it’s dangerous for the country and I don’t want to put the country in that spot,” McCusker said. “People say you give a vote to Hillary or Bernie, but at least I can go to sleep at night.”

Don Merchand, 49, clad in a T-shirt with Ronald Reagan’s face on it, said he supports Cruz but could see backing Trump. Merchant said he is happy the two aren’t buddying up to one another any more.

“I thought they were too nice to each other, that Donald Trump was supporting Ted Cruz,” Merchand said. As for Cruz, “I don’t think he wants to insult many Trump voters because they might come to him.”

No matter what has happened in a very long Republican primary season, Marchand said, voters in New Hampshire will finally start to pay attention as the Feb. 9 primary approaches.

“People aren’t going to pay attention until next week or a week after,” he said.