Have any Democrats embraced any new policies or compromises in an attempt to appeal to conservatives that are unhappy with Trump?

Question

When Trump was nominated as the presidential candidate in 2016, there was a major shift in the Republican party away from classically-liberal small-government party towards a more populist, nativist party. Because of this, many conservatives felt alienated and no longer at home in the GOP. For example, in 2016 Mitt Romney gave a long speech on the dangers of Trump's policies:

His tax plan in combination with his refusal to reform entitlements and honestly address spending would balloon the deficit and the national debt. So even though Donald Trump has offered very few specific economic plans, what little he has said is enough to know that he would be very bad for American workers and for American families...

Now let me turn to national security and the safety of our homes and loved ones. Mr. Trump's bombast is already alarming the allies and fueling the enmity of our enemies. Insulting all Muslims will keep many of them from fully engaging with us in the urgent fight against ISIS, and for what purpose?

Arguably, this group is shrinking in relevance as more right-leaning Americans sign onto Trump's agenda, but presumably there are still some conservatives dissatisfied with the deficit, expanding executive power, lack of respectful discourse, and focus on stopping immigration coming from the white house. In a recent interview, noted Never-Trump Republican Bill Kristol said that if Trump gets the GOP nomination he "wouldn’t rule out voting for Democrat against Trump at all.”

My question is this: Have any Democrats in leadership or candidates for office, embraced any new policies or compromises in an attempt to appeal to conservatives that are unhappy with Trump? For example, a presidential candidate might offer to nominate a supreme court justice with a narrow/textual view of the constitution in order to undermine one of Trump's key appeals among conservative voters.

Answer 1

Probably nothing of this counts as outright new policies, but should it give you an idea where the debate is in the Democratic camp in terms of appealing to the center and/or moderate Republicans; this info is a bit dated based on polls from this summer, but should still relevant nonetheless:

Many progressives have written off Republican voters, deeming them unpersuadable. That���s a mistake. In the YouGov survey, 42 percent of Republicans disapproved of separating undocumented immigrant families. In the Marist survey, 35 percent of Republicans supported a pathway to citizenship, and 46 percent endorsed “Medicare for all that want it.” In the Fox survey, 51 percent of Republicans favored “changing the health care system so that every American can buy into Medicare if they want to.”

So, for example, the Biden/Buttigieg approach to healthcare, which has a public option (that Obama's initial 2008 plan also had, although Obama later dropped that public-option part) seems reasonably palatable to some Republicans... and overall has more appeal than "medicare for all":

The Marist respondents strongly preferred moderate to radical ideas. Fifty-four percent opposed a Medicare for All program that “replaces private health insurance,” but 70 percent supported “Medicare for all that want it,” a program that would let people “choose between a national health insurance program or their own private health insurance.” Two-thirds supported a “pathway to citizenship” for undocumented immigrants, but 66 percent opposed “decriminalizing illegal border crossings,” and 62 percent opposed a “national health insurance program available for immigrants who are in the US illegally.”

On some narrower issues of immigration like non-separation of illegal immigrant children from their families probably all Democrats appeal to some Republicans, although those narrower issues might not be very important, unlike healthcare. (I don't quite know how the Democratic candidates [try to] differentiate from each other on immigration. One headline was that "Trump’s extremism is helping 2020 Democrats avoid the really hard questions on immigration.")

As far as free trade goes, it seems that Biden was perceived as the candidate most favorable to that (from the Democratic camp), definitely more so than Warren or Sanders, and perhaps more so than Buttigieg as well.