Some people call this Tuesday Super Tuesday II, as its slate of primaries forms a sequel of sorts to the mammoth run of contests held on the first such day in March. Others refer to Mega Tuesday, Big Tuesday or even, in 2016 at least, the Ides of March Primaries.

Either way, it’s another brutal day in the race for the Democratic presidential nomination. Here’s a quick guide to what’s happening:

Who’s voting

Michigan, Mississippi, Missouri, Idaho, North Dakota and Washington state all host primaries.

Who’s giving

Michigan is the richest prize on offer, with 125 delegates. Washington state offers 89, Missouri 68, Mississippi 36, Idaho 20 and North Dakota 14.

Who’s closing

Polls close in Michigan, Mississippi and Missouri at 8pm ET, in Idaho and North Dakota at 10pm ET and in Washington at 11pm ET.

Who’s running

Former vice-president Joe Biden, Vermont senator Bernie Sanders and, lest the national media forget, Hawaii congresswoman Tulsi Gabbard.

Who’s polling

Most eyes have been on Michigan, where Biden has opened a lead north of 20 points over Sanders in recent polls. According to the forecasting site fivethirtyeight.com, the former vice-president is favourite to sweep the board – though it expects most races to be tight.

Who’s winning

After his Super Tuesday surge, Biden has garnered 670 delegates to the Democratic national convention, Sanders has 573 and Gabbard has two. To win the nomination outright at the event in Milwaukee in July, a candidate will require 1,991 of the pledged party delegates who typically anoint the nominee, a plain majority.