ARI SHAPIRO, HOST:
Now we're going to look at some of the political implications of the FBI's announcement as well as some of the other big trends to watch for on Election Day. NPR national political correspondent Mara Liasson is here in the studio. Hi, Mara.
MARA LIASSON, BYLINE: Hi, Ari.
SHAPIRO: Let's start with the FBI, James Comey and Hillary Clinton's emails. What kind of effect has this final twist had on the campaign (laughter) and not to mention the events leading up to it?
LIASSON: Well, on the presidential race horse race, it doesn't look like it has had much of effect at all. According to the Clinton campaign, they are pretty much on track to where they were before. However, it did deprive Hillary Clinton of nine days of having a positive, affirmative message.
Democrats say where it did hurt them was down ballot because it accelerated Republicans coming home to Trump, delayed Democrats coming home. They say that damage was done by Comey's reopening of the investigation and can't be undone by his letter on Sunday.
For the Trump campaign, the whole episode was a morale booster. It gave Donald Trump a big talking point all last week. But when you're dependent on external events for momentum, you're not really in charge of your own fate. And the Trump campaign learned the hard way that what Comey giveth, he can taketh away.
SHAPIRO: Let's talk more broadly about these final 24 hours. Millions of people have already voted early. What do those numbers tell us, if anything?
LIASSON: It's going to be a while to know what the early vote means because the rules and the laws about early voting are changing, and we don't have a good baseline to compare them to.
For example, we had some reports that African-American enthusiasm is down based on the early vote data. Well, we know that African-American voters don't have as much organic enthusiasm for Hillary Clinton as they did for Barack Obama, but it's also true that in states like North Carolina, there are now fewer voting stations and fewer days of early voting. So maybe that's the reason there was a drop off.
We know for instance that the Hispanic vote is way up in early voting in Nevada and North Carolina and Florida, but Hispanics have traditionally underperformed their share of the eligible vote population. They usually turn out less than 50 percent. So is that going to change this year? We don't know yet. We do know that the Clinton campaign has been making early voting a big priority out of necessity since Democratic voters are generally harder to turn out than Republican voters.
SHAPIRO: We've also seen a big difference between the two campaigns' get-out-the-vote operations, the ground game. Now, while the Clinton campaign has put a lot of energy into the ground game and data analytics, Trump has focused more on big rallies and social media. How much do you think that might matter tomorrow?
LIASSON: We're going to find out. You know, the rule of thumb is - the conventional wisdom is that a good ground game can give you one to two points more vote, and that can make a big difference in a close race. But we have never had a controlled experiment like the one we're having this time with one campaign - the Democrats - having the biggest, best, most sophisticated ground game money can buy.
And on the other side, Donald Trump has said he thinks big data and analytics are overrated as a way to get out the vote. He'd rather hold big rallies and dominate social media. He has a tremendous amount of organic enthusiasm. And without that, no ground game can make a difference. It would be like pushing on a string.
But Trump has pretty much farmed out his entire ground game to the RNC. So in the past, we've seen candidates who by sheer force of will and charisma heave their campaigns over the finish line. We've also seen campaigns that because of a great field operation can heave a less-than-inspiring candidate over the finish line. We're going to see this time which model wins.
SHAPIRO: Beyond the presidential race, what are you going to be looking for down ballot tomorrow in the House and Senate contests?
LIASSON: Well, certainly who wins the Senate - do the Democrats get the net four pickups they need if Hillary Clinton wins the presidential race? That would give them the majority in the Senate. How many seats do Republicans lose in the House? No one thinks Democrats will win the net 30 they need to take the majority there, but I think more than 15 pickups for the Democrats is a good night for them. Less than 15 is a good night for the Republicans.
But I'll also be watching to see the difference in the margins between Republican Senate candidates and Donald Trump in their states. In other words, do they outperform him? Does he...
SHAPIRO: How many ticket splitters are there?
LIASSON: Right - how many ticket splitters? Do - does he drag Republican Senate candidates down, or do they outperform him? That would suggest that the Republican brand is somewhat separate from the Donald Trump brand.
And you know, we talk a lot about the down-ballot effects of a popular or unpopular presidential candidate. This year we may be seeing up-ballot effects. In other words, does Rob Portman running for Senate in Ohio who's built a great field operation - does he actually help Donald Trump?
SHAPIRO: NPR's Mara Liasson, thanks a lot.
LIASSON: Thank you. Transcript provided by NPR, Copyright NPR.