Updated

Even as he is embroiled in a dispute that may leave him out of the Republican debate Thursday night, Donald Trump is breaking from his reputation as a flame-throwing outsider with just days to go before Iowa's leadoff caucuses, highlighting his willingness to work with Democrats in Congress as part of a closing argument with a distinctly bipartisan tone.

The billionaire businessman's promise to get things done in Washington is a direct contrast to leading GOP rival Ted Cruz, the Texas senator whose brief Washington career has been defined in part by his inability to get along with his own party. Trump's can-do message comes as adversaries begin pouring money into tough ads questioning his commitment to conservative values — attacks that some in the GOP's establishment wing have long awaited.

It's unclear whether it's too little and too late to stop Trump as he tries to become the first Republican in modern political history to win opening primary contests in both Iowa and New Hampshire.

Trump is doing plenty of his own attacking.

"I don't think he'll get anything through Congress because everybody hates him," Trump said of Cruz Tuesday on MSNBC's "Morning Joe."

Trump claimed to have good relationships with such top congressional Democrats as Nancy Pelosi and Chuck Schumer, predicting he could get things done in a way Cruz could not.

"Ted Cruz lies. He is a liar. That's why nobody likes him," Trump said. "That's why he stands on the middle of the Senate floor and can't make a deal with anybody. ... And you know, there's something to say about having a little bit of ability to get other people to do things.

The change in message is playing out against the drama of Thursday night's debate, which is being hosted by Fox News and is to be moderated by Megyn Kelly, an anchor that Trump locked horns with earlier in the campaign. The candidate has indicated that he may stay home rather than participate unless the network replaces her.

In some ways, Trump's message plays into the hands of his Republican critics, who have long questioned his willingness to stick to conservative principles. Such questions are the focus of a burst of concentrated ads coming from an unusual coalition of Cruz boosters and mainstream GOP figures.

Cruz allies have circulated no fewer than six anti-Trump ads in recent days, the bulk of the advertising coming from super political action committees in a billionaire-funded network called Keep the Promise.

"Donald Trump is not a conservative," one of the ads charges before looping footage of him in 1999 declaring, "I am pro-choice in every respect." Trump says he has since changed his position and opposes abortion rights. That commercial is part of a $2.5 million TV ad buy in Iowa and South Carolina.

Another Keep the Promise ad released on Tuesday proclaims, "Donald Trump will make very bad deals with Democrats." It shows him saying, "Let's get to be a little establishment. We've got to get things done, folks, OK?"

Cruz's own campaign has a new Iowa ad out that hits Trump for having "New York values." That commercial also has a clip of the businessman saying, "How stupid are the people of Iowa?" — an insult he hurled after his poll numbers dipped in an earlier survey.

Some mainstream Republicans have joined the Trump pile-on.

Katie Packer, a senior aide to Mitt Romney's 2012 campaign, launched a super PAC in recent days that's spending hundreds of thousands of dollars for an Iowa-focused anti-Trump campaign that includes television and radio ads in addition to mailers.

"I'm not a big Ted Cruz fan, but I believe that Donald Trump represents a long-term threat to our party beyond just losing the general election," Packer said. "If we nominate a guy without any anchor on our core issues, we've essentially nominated a Democrat."

Backers of other Republican candidates are spending big on negative ads, too, as they fight for support as the establishment alternative to the two front-runners.

Outside groups aiding former Florida Gov. Jeb Bush, Florida Sen. Marco Rubio, Ohio Gov. John Kasich and New Jersey Gov. Chris Christie have spent more than $36 million on ads that largely focus on tearing each other down, data from ad tracker Kantar Media's CMAG show. Those groups are spending hundreds of thousands of dollars more on direct mail and digital ads along the same lines, according to filings with federal election regulators.

Those four candidates are vying to be a surprise winner in New Hampshire, the second-to-vote state. Trump is polling at the top of the field there, too.

And all the while, some high-profile conservatives are rallying behind Trump, who has thrilled many in the Republican base with aggressive plans to crack down on illegal immigration and ban Muslims from entering the country, at least temporarily, to safeguard against terrorist threats.

After winning former Alaska Gov. Sarah Palin's endorsement last week, Trump on Tuesday announced the backing of Christian conservative leader Jerry Falwell, Jr., the son of the late televangelist. Maricopa County Sheriff Joe Arpaio, whose fame has spread beyond Arizona thanks to his hard-line stance against immigrants in the country illegally, joined Trump at a rally Tuesday in Iowa.

Cruz, too, has unveiled big-name conservative support in recent days, commentator Glenn Beck and former Texas Gov. Rick Perry among them. Yet Falwell's support for Trump may particularly sting.

Falwell is the president of Liberty University, where Cruz formally launched his presidential campaign. Backing from such well-known conservatives could give Trump political cover to promote his relationships with Democrats.

"I've always had a good relationship with Nancy Pelosi. I've never had a problem," Trump said of the House's top Democrat. He said he's "always had a decent relationship" with top Senate Democrat Harry Reid and was "close to" third-ranking Chuck Schumer.

"It's important that you get along," Trump said.

Like us on Facebook
Follow us on Twitter & Instagram