Analysis by Chris Cillizza

Editor-at-large

(CNN) -- Eighteen candidates are running in the special election primary to replace Health and Human Services Secretary Tom Price in Georgia's 6th district on Tuesday. But only one is drawing national attention: Democrat Jon Ossoff. Democrats see a path for Ossoff to get 50% of the vote on Tuesday and win the seat outright, a result that would suggest the Republican-controlled House is in serious danger next fall. (President Donald Trump won the seat narrowly last November, but it has been reliably Republican for decades.) Trump even tweeted about the race on Monday morning.

For an on-the-ground sense of where the race is and where's it going, I reached out to Atlanta Journal-Constitution political reporter Greg Bluestein. Our conversation, conducted via email and lightly edited for flow, is below.

Cillizza: Democrats seem to be scaling back expectations that Ossoff might get to 50% tomorrow. Is that just expectation setting or does the evidence on the ground suggest he's slowing?

Bluestein: The latest round of public polls show Ossoff in the low-to-mid 40s and internal Democratic polls don't show him much higher. And Republican-leaning voters caught up to an initial Democratic lead in early voting. Republicans who were unbelievably skittish just a week ago are sounding much more confident, while Ossoff backers privately say they were always gunning for a runoff even if publicly he says an outright win is still within reach.

Cillizza: Should this district be competitive? Trump barely won it, but Republicans have held it for decades. What sort of voters live there?

Bluestein: That's what makes this race so fascinating: It shouldn't be competitive. When Rep. Tom Price was tapped as Donald Trump's health secretary, Georgia politicos were readying for what was likely to be an all-Republican fight featuring a few token Democrats. But Ossoff has jolted the 18-canddiate field and unified most of the district's Democrats and Trump skeptics. That said, he faces long odds. Price won this district by landslide victories every two years, and before that portions of it were represented by Newt Gingrich and Johnny Isakson. It's an affluent, highly educated and establishment-friendly district along Atlanta's northern 'burbs where Chamber of Commerce-type Republicans usually prevail.

Cillizza: The focus is all on Ossoff. But which Republican do you think makes it into the runoff with him (if there is one)? And, why?

Bluestein: There are 11 Republicans in the race, but four have emerged as leading contenders: Karen Handel, Bob Gray, Dan Moody and Judson Hill. Handel has emerged as the most probable Republican to land in the runoff. A former Georgia secretary of state, she benefits from tremendous name recognition in the district from two other unsuccessful statewide runs: She narrowly lost a GOP runoff for governor in 2010 and finished in third in the Republican primary for an open US Senate seat in 2014. But the other three Republicans have more money than her and a wider ad presence. And Gray, in particular, is an interesting test case: He's running as a pro-Trump loyalist with a promise to be a "willing partner" to the President.

Cillizza: Conventional wisdom is that Ossoff's best (and maybe only) chance to win the seat is Tuesday, not in a runoff. True? And does it matter who Republicans nominate?

Bluestein: It's his best chance, but not his only chance. Ossoff's campaign is trying to exploit the vicious internal feuding among Republican candidates, who are attacking each other more than him. In a runoff, Republicans would be pressured to get over their infighting and unify behind whoever emerges. The full weight of the GOP would likely be behind that candidate, and Ossoff would be faced with another uphill battle, working against demographics and voting history that do him no favors. But Republican unity is no given. This race has been particularly vicious on the GOP side, and Handel -- if she lands the No. 2 spot -- has few close allies in the ranks of Georgia Republican leadership. Most of the big names in the Georgia GOP - (Sen.) David Perdue, Gingrich, (Gov.) Nathan Deal -- have either endorsed her competitors or stayed out of the race.

Cillizza: Finish this sentence: "If Ossoff wins more than 50% Tuesday, it tell us _ about the national political environment." Now, explain.

Bluestein: It tells us how Trump-ified the national political environment is. We already knew that Republicans in swing House districts in 2018 would have to play defense on Trump. But this district was anything but a swing district -- just months ago it was considered the safest of safe GOP seats. Mitt Romney and John McCain won it by overwhelming margins in 2012 and 2008, and it's so red that many Democrats didn't even stand for legislative seats or local offices in November. But Trump's tepid support in the district and Ossoff's out-of-nowhere campaign may be the first big test of the Trump resistance -- or just another close call for frustrated Democrats.