A Look at the Stakes in West Virginia and Nebraska Primaries

Breaking down the delegate counts.

There are 70 delegates up for grabs for Republicans tonight: 36 in Nebraska and 34 in West Virginia.

The Nebraska race stands to be a windfall as the delegates are allotted on a winner-take-all basis. Nine of the West Virginia delegates are allotted based on the popular votes in the state's three congressional districts, with each district controlling three delegates. The remaining 25 at-large delegates are determined by delegate preference.

Neither of the primary races will be fully firmed up because of the outcomes of tonight's primaries.

In order to win the nomination using all remaining delegates, Clinton would have to win 16 percent the rest of the way and Sanders would have to win 97 percent.

That gap shrinks slightly if limited to pledged delegates only, in which case Clinton would have to win 34 percent of the remaining delegates while Sanders would need 66 percent.

All told, Clinton is much closer to securing the nomination. She has won about 93.5 percent of the 2,383 delegates necessary for the nomination. Sanders has won about 61 percent of the 2,383 necessary.

The ABC News analysis indicates Trump now has 1,077 total delegates.