To embrace Donald Trump or not embrace Donald Trump?
That is the question many Republicans and their leaders are wrestling with as the presumptive nominee prepares to visit Capitol Hill on Thursday as he seeks to build closer alliances with top GOP officials.
Over the past four months, as Trump kept winning GOP primaries, congressional Republicans divided into four camps.
A small bloc of House members and Alabama Sen. Jeff Sessions enthusiastically backed him.
A rival but equally small group, led by Nebraska Sen. Ben Sasse and later joined by South Carolina Sen. Lindsey Graham, said they would never vote for the real estate mogul.
Another group, including House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell, publicly announced their differences with Trump on specific issues and the overall tone of his campaign rhetoric, while leaving open the possibility of backing him later.
And a fourth group has essentially stayed silent, or in the case New Hampshire Sen. Kelly Ayotte, tried to have it both ways: saying she will "support" Trump but not "endorse" him.
Whatever their positions, many of those Republicans will be focused most on their own self-preservation. And the reticence to fully embrace Trump reflects concerns that the candidate, if he maintains his current unpopularity in the polls, could not only lose the presidency but cost Republicans in Congress their jobs too.
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"If I was a GOP House or Senate candidate in a battleground state I'd be searching for a 3rd alternative to back. Trump's #s are toxic," said longtime GOP operative Brian Walsh on Twitter last week.
Walsh had been a top operative in the national Republican Senate campaign operation in 2010 and 2012.
The GOP has sizable majorities in both the House and Senate, but most Americans are likely to vote in November for congressional candidates from the same party as the presidential candidate they support.
So if Trump loses badly to Hillary Clinton, the way John McCain did to Barack Obama in 2008, Democrats could sweep into power in Congress as well. Democrats will need to gain 30 seats in this fall's elections to get a majority in the House, and five seats for a Senate majority. Senate Republicans are particularly vulnerable, with six seats up in states that Obama won in 2012.
"The Senate these days tends to follow the top of the ticket, so if Trump loses the states where GOP senators are up for re-election, most if not all will also lose," said Henry Olsen, a senior fellow at the conservative Ethics and Public Policy Center.
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"The House," he added, "is less partisan, although still highly so."
Mark Graul, who ran President Bush's 2004 reelection operation in Wisconsin, told the Milwaukee Journal Sentinel this week, "The big concern I have at this early stage is ... if (Trump's) presence on the ballot is going to depress Republican turnout."
For now, even as party strategists acknowledge wariness about Trump's potentially-negative impact on the rest of the party, Republican officeholders are not fretting publicly.
Asked on Tuesday about the prospect of Trump causing his colleagues to lose their seats, McConnell downplayed the issue, citing some new polling released this week by Quinnipiac University that show Trump effectively tied with Clinton in some key swing states.
"It looks to me, at the beginning of the race, Florida and Ohio look competitive," said McConnell, who until recently had been taking steps to stop Trump from winning the nomination.
But he added, in a nod towards the unpredictability of this campaign, "we'll see."
Tom Cole, a House Republican from Oklahoma who used to run the party's re-election arm for the House, emphasized that House members have "distinct identities" in their congressional districts and are not defined completely by the person at the top of the ticket.
"We have done a good job positioning our members," said Cole, noting few House Republican incumbents have lost in primaries this year, even as Trump has defeated the party establishment's presidential hopefuls.
"Now, we'll just have to go through the storm," he added.
Trump seems to understand that GOP officials may be wary of him because of their individual electoral concerns. In a Twitter message on Tuesday, Trump said he was excited about meeting with congressional Republican leaders, adding, "together, we will beat the Dems at all levels."
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No matter what happens at Thursday's meeting, Republicans on Capitol Hill have already taken a number of steps to establish that they are independent of Trump's policy ideas and rhetoric.
House Republicans, led by Ryan, are coming up with a list of policies they will campaign on this fall. According to GOP sources, the agenda will almost certainly not include Trump's ideas about building a wall between the U.S. and Mexico or banning Muslims from entering the United States.
Ryan and his team are hoping Trump borrows from their ideas and puts them in his platform, instead of the traditional process of the presidential nominee setting the agenda for the rest of the party.
"We have to be a party that is — that is broad and inclusive, principled, applies those principles to the problems of the day, offering the country better solutions, and actually appeals to independents and disaffected Democrats," Ryan said in an interview with the Wall Street Journal in which he was asked about the upcoming meeting with Trump.
He added, "Donald Trump brought a lot of disaffected Democrats and independents into the party through these primaries. So I think the seeds are there."
The head of the National Republican Senatorial Committee, the campaign arm for Senate Republicans, has urged GOP senators in swing states to act as if they are "running for sheriff" in their communities, emphasizing local issues and avoiding discussion of the presidential campaign when possible. Many Republicans in swing states have already said they will not attend July's Republican National Convention in Cleveland, avoiding an event that will likely celebrate Trump.
"Trump was not my first, second, or third choice. I object to much in his manner and his policies. His vulgarity, particularly toward women, is appalling. His lack of appreciation for Constitutional limits on executive powers is deeply concerning. I disagree with his proposals to ban Muslims," wrote Pennsylvania U.S. Senator Pat Toomey in an op-ed this weekend in the Philadelphia Inquirer titled "Advice to Trump: Seek to unite and listen more."
This was the latest move by Toomey, a Republican in a state where Democrats usually win in presidential elections, to illustrate to Keystone State voters that he is distinct from Trump.
Toomey would have faced a difficult reelection no matter what, because of Pennsylvania's liberal bent. But the House had long been assumed to be safe for the GOP, until polling showed Trump's very low levels of support among people of color and white women. He is by some measures the most unpopular serious presidential candidate in modern times.
A radical shift in the makeup of the House is entirely possible in theory, since Democrats gained 30 seats in 2006, while the GOP won control of 63 in 2010.
This story originally appeared on NBCNews.com.