Editor’s note: The presidential nominating contests in both parties will come down to the California primary.

For Democrats, 548 delegates are at stake — 11.5% of the total. For Republicans, 172 delegates are at stage — 6.9% of the total. Of those, for Democrats, 158 (29%) are divided proportionally on a statewide basis, while 317 (58%) are divided proportionally by congressional district, with each district providing between 5 and 8 delegates. The remaining 73 (13%) are “superdelegates.”

For Republicans, 13 (8%) are awarded statewide, with ten going to the candidate with the highest number of votes on a winner-take-all basis, and three going to “pre-determined” delegates (the State Chair, National Committeewoman, National Committeeman). Meanwhile, 159 (92%) are awarded by congressional district on a winner-take-all basis, with each district providing 3 delegates.

The result: a district-by-district battle in both parties, which we preview for you here.

CA-21: This district follows the path of the California Aqueduct and the Central Valley Project to the southeast, along with Interstate 5 through the Central Valley’s rich, irrigated farmlands. The district is represented by moderate Republican David Valadao, who participated in an all-Spanish debate in the 2014 election. Over two-thirds of the district is Latino, and more than 95% of those residents are from Mexico, a key clue to its political orientation.

Prospects:

Democrats: Clinton should sweep this district, given its conservative politics and large Hispanic population.

Clinton 4, Sanders 0

Republicans: This is prime Ted Cruz territory — or, at the very least, very receptive to anti-Trump politicians.

Cruz 3, Trump 0, Kasich 0

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. His new e-book, Leadership Secrets of the Kings and Prophets: What the Bible’s Struggles Teach Us About Today, is on sale through Amazon Kindle Direct. Follow him on Twitter at @joelpollak.