No one agrees why.
The amount of rationalization that one has to engage in to excuse Trump's behavior feels less like a political ideology and more like pathology.
On the ground, it's been a coalition of anti-Trump groups, many that sprouted after Trump's election and led by women, that have been the volunteer backbone of the Lamb campaign. "I'll work with anyone from either party who wants to help people with pre-existing conditions, improve the quality of care, and reduce premiums, out-of-pocket costs, and prescription drug prices", he says on his campaign website. "He has no record, c'mon on", Saccone said.
Not only did the president campaign for Moore, tweet for Moore - but Trump essentially saved Moore's campaign after numerous and detailed sexual assault allegations were leveled against the Republican candidate.
Cillizza: Where did Lamb come from? Registered Democrats still outnumber Republicans by nearly a four-to-three ratio in a district where gun rights are a high priority, and Democrats still hold some local offices.
AFL-CIO chief Richard Trumka is weighing in on behalf of Democrat Conor Lamb. Conor's father worked in the Congress in the 1980s for US Rep. Austin Murphy, and is now a well-connected top government affairs officer for PNC, the nation's ninth largest bank.
But Washington is often guilty of hyperventilating about a special election. He's up against 33-year-old Conor Lamb, who pitches himself as an independent-minded Democrat.
A 68-year-old retired engineer who described himself as a "John Kasich-Daddy Bush Republican", Bruce Bancroft said he always voted for Murphy, but finds Saccone too strident for the district and an already acrimonious Congress.
Republicans in the Trump era had found similar fault with other struggling candidates.
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Auburn (2-3 in those games) defeated the Pride, lost to the Owls and Gators, and split with the Gamecocks. This year marked the first time since 1999 that any of those things have happened on the Plains.
The most money spent on a special House race - or any House race - was $55 million a year ago in suburban Atlanta, in Democrats' failed effort to take a GOP-held seat.
Ironically, Reschenthaler would have looked a lot more like Lamb.
Following last month's shooting in Parkland, both Saccone and the NRA alike attempted to shift focus from guns to "failings" on the part of law enforcement, which the NRA has blamed for dropping the ball, despite being warned of the shooter's troubling behavior months earlier.
An 11th hour visit by President Trump, more than $10 million of Republican campaign spending, and a coordinated labor union effort for Lamb have put the national spotlight on a district that Trump won by almost 20 points in 2016. The chairman of the state party said that the district, held since 2003 by a Republican, is a "Democrat district".
Lamb has a run as a moderate with considerable union backing. Do you see evidence it's working?
After more than 13 years as the House Democratic leader, Pelosi has written enough feminist history to fill the Capitol dome. In general, the outside PAC attack on Lamb has struck many as so over-the-edge as to be unbelievable. Lamb claims that he is personally opposed to abortion but is supportive of so-called abortion rights. "What happens here will set the stage for the critical midterm elections coming this November - especially in states like Ohio, Pennsylvania, Michigan, Indiana and Wisconsin - all states where Democratic senators are seeking re-election".
National Republicans have started to distance themselves slightly from Saccone in case of a loss blaming Saccone's lack of fundraising and poor campaign organization rather than their efforts or any negative impact from Trump's policies.
Trump Jr. repeatedly told reporters that the president's agenda would be on the ballot on Tuesday. "I won this district by 22 points".
The contest is drawing so much national attention because of its potential to preview a change in the political landscape in the upcoming midterm elections.