Will anyone watch the Democratic debate tonight?

From left: US Senator Bernie Sanders, Hillary Clinton, and Martin O’Malley participated in a December debate. Richard Perry/New York Times

Sunday night’s presidential debate should be the most closely-watched meeting of the party’s candidates this year. But once again, thanks to the Democratic National Committee’s schedule, debate viewership will not be even close to what it could have been.

The 2016 Democratic presidential contest has been never been more competitive. This week, new polls showed former US secretary of state Hillary Clinton and US Senator Bernie Sanders of Vermont statistically tied in Iowa. The contest has become increasingly intense, with both Clinton and Sanders releasing new television ads this week that needle each other for the first time.

This alone would mean that the next Democratic debate could be the most important yet in the contest. What’s more, this is the last debate before the Iowa caucuses and the New Hampshire Primary.

But not only will this debate air at 9 p.m. on Sunday, in the middle of a three-day weekend, but it will also run during National Football League playoff games and — dare we say — a new episode of PBS’s popular series, “Downton Abbey.”

It’s not new for debates to run on a busy weekend night. But this is by design: Of the six DNC-sanction debates, three take place on a weekend night. The last one took place on a Saturday night six days before Christmas.

Ahead of that December debate, the Globe interviewed DNC chairman Debbie Wasserman Schultz. She said television stations dictated the debate times.

But apparently the Republican National Committee did not have the same problem: Just two of the 10 Republican debates will take place on a weekend. And there’s still more sense in the timing of those weekend debates: Those occur days before the New Hampshire and South Carolina primaries.

When these debates air matters a lot in ratings. When the first Democratic debate aired on CNN on a Tuesday, 15.6 million watched. When the last two debates aired on CBS and ABC on Saturday nights, the ratings were 8.5 million and 7.85 million, respectively.

Compare this with the Republican debates, which have been a ratings bonanza (thanks mostly to the front-runner, Donald Trump). The Republican debate on Las Vegas in December (on a Tuesday) had 18 million viewers.