(CNN) In the past week -- amid allegations that President Donald Trump abused the power of his office for personal political gain -- there has been an absolute rush among House Democrats to call for impeachment proceedings against the President. What was once regarded as a risky position, politically, has now become a default position of the vast majority of the Democratic caucus.

But interestingly, it's not the position of the entire caucus. Yes, 223 House Democrats are on the record supporting an impeachment inquiry. But 12 holdouts remain.

Why? Good question! As (almost) always in politics, the answer to that question is, well, politics. Of the 12 holdouts, 11 represent districts that Trump carried in 2016. Trump's winning margin in those 11 ranges from quite narrow (+1.5 percentage points in Rep. Lucy McBath's suburban Atlanta seat) to huge (+31 in Rep. Collin Peterson's rural western Minnesota seat).

The one outlier in the group is Rep. Eddie Bernice Johnson (Texas). Trump lost Johnson's seat by 61 points in 2016.

Johnson is a bit of a unique case as some outlets -- including the Texas Tribune -- count her as in favor of impeachment. CNN does not because, in her statement on the subject, Johnson made her support for impeachment conditional. "If the decision is made by the President and his Administration to withhold this information from Congress, or if the allegations of his abuse of power are substantiated, I will be placed in a position where I must fulfill my constitutional duty and support impeachment proceedings," she said. The whistleblower complaint has now been turned over to Congress so it remains to be seen where, exactly, Johnson now comes down on impeachment.

Below, a full list of the 12 impeachment holdouts -- and their stated reasons (where we have them) for why they are holding off in making a full-throated call for the impeachment of Trump. (In parentheses, is the Trump margin in each of their districts.)

* Rep. Lucy McBath (Georgia): According to the Atlanta Journal Constitution: "As I have continued to say from the beginning - the Judiciary Committee's investigation has always been to find the facts for the American people. I voted to formalize the impeachment inquiry process on September 12th and continue to support the responsibility of this Congress to uncover the truth and defend the Constitution."

(Trump +1.5)

* Rep. Jared Golden (Maine): According to the Bangor Daily News, Golden said this at a recent constituent meeting: "We didn't get one question about impeachment, about Mueller, about 'the squad' (four minority women members of the House of Representatives), about socialism versus Donald Trump — none of this BS that I think drives the silent majority of Americans absolutely insane." On Friday, he said in a statement: "I will have more to say in the coming days as I continue to carefully weigh the information we received this week and consider what I believe to be the best next steps for the House." (Trump +10)

* Rep. Collin Peterson (Minnesota): In a statement, Peterson said: "If anyone thinks a partisan impeachment process would constrain President Trump, they are fooling themselves. Without significant bipartisan support, impeachment proceedings will be a lengthy and divisive action with no resolution." (Trump +31)

* Rep. Jeff Van Drew (New Jersey): Here's what Van Drew told The Washington Post this week: "I wish we waited a little longer. I wish we looked at it a little more — continuing the investigation, continuing the hearings that we've had. I just didn't want to go down the impeachment route." (Trump +5)

* Rep. Xochitl Torres Small (New Mexico): In a statement released this week, she said this: "Through the coming weeks and months, I will act to support and defend our Constitution by insisting on a transparent process that fully informs the American people and restores trust and faith in our system. This is a threat to our national security, and it must be taken seriously." (Trump +10)

* Rep. Max Rose (New York): A Rose statement this week read: "That there is such a lack of trust is a damning indictment of both parties and why I ran for office in the first place. It's also why I have opposed a partisan impeachment process that would only deepen those divisions, not solve them." (Trump+10)

* Rep. Anthony Brindisi (New York): "I'm not rushing to judgment on anything. I'm not responding to pressure from social media, I have a job to do, that's to uphold the constitution, and I intend to do that," Brindisi told CNYCentral this week. (Trump +16)

* Rep. Kendra Horn (Oklahoma): From Horn's office: "She believes Congress and the American people deserve to know all of the facts before jumping to conclusions. The whistleblower law calls for a process to determine what happened and when. The Congresswoman believes this process should be conducted in a detailed, methodical, and responsible manner before any Congressional inquiry is initiated." (Trump +13)

* Rep. Joe Cunningham (South Carolina): "We need to be careful not to get ahead of the evidence and be as deliberate and judicious as possible during this process, while following the facts where they lead," Cunningham told the Charleston Post and Courier this week. (Trump +13)

* Rep. Eddie Bernice Johnson (Texas): See above (Trump -61)

* Rep. Ben McAdams (Utah): Said McAdams in a statement: "The phone call summary released by the White House today suggests the president was improperly using his influence with a foreign power to damage a political opponent. On this and other matters we need to get all the facts on the table before deciding how to proceed." (Trump +7)

* Rep. Ron Kind (Wisconsin): Kind said earlier this week that the whistleblower allegations are "very concerning" but didn't mention impeachment in his statement. Back in May, at an event in Wisconsin, Kind explained his thinking this way: "Whether it elevates to the level where you have bipartisan support to pursue impeachment proceedings, that question really needs to be directed toward my Republican colleagues, who all seem to be circling the wagons and protecting this president from any type of oversight or any type of scrutiny." (Trump +4)