On the GOP side, Trump led the pack with seven victories, while Ted Cruz picked up three, including his home state of Texas. Rubio scored his first win of the season, in the Minnesota caucuses.
With some Tuesday night allocations still outstanding, Trump now leads the Republican field with 332 delegates. Cruz, at 230, sits in distant second and Rubio's 113 are good for third. John Kasich has just 27 delegates and Ben Carson, who will no longer be actively campaigning, has seven. A majority of the 2,472 total delegates -- 1,237 -- is needed to win the nomination. Although the nominee is not officially selected until the delegates meet and vote at the Republican National Convention. Here's how the race could go:
There will be opportunities for the underdogs to shake up the race in the coming weeks.
March 15 is the first date to watch. Until now, states have split their delegates between all of the finishers who reach a certain threshold. But primaries in delegate-rich Ohio and Florida are winner-take-all, meaning even a narrow victory for Rubio in his home state would net him a potentially game-changing 99 delegates. Same for Kasich, the Ohio governor, who stands to add 66 delegates if he can win his Buckeye State. Those are big ifs, since Trump appears strong in recent polling in both states.
In April, New York's 95 delegates will be distributed proportionally, as will California's 172 when it votes on June 7. Montana, New Jersey and South Dakota will award a total of 107 delegates in winner-take-all primaries on the same day, the last one on the primary schedule.
But with Cruz and Rubio pledging to stay in the race for the long haul (Kasich has suggested he will drop out if he loses Ohio), Trump's path to the nomination is looking clearer with every passing contest.
Clinton has wide delegate lead, trove of "superdelegates"
Meanwhile, the Democratic race is beginning to shape up like a rout. With the help of a heavy slate of superdelegate support, Clinton is nearly halfway to a clinching majority. She currently holds 1,055 delegates, 587 of them pledged. Sanders has 418, with 397 bound to back him.
Here's what their race -- to a 2,383 delegate majority-- looks like on Wednesday:
Sanders' path is especially narrow because the Democratic Party does not offer any winner-take-all or hybrid votes. Every contest awards its delegates proportionally, so the Vermont senator will need to score significant victories on March 15 in the delegate-heavy Florida, Illinois and Ohio contests if he hopes to upend Clinton. Sanders will also look to a glut of caucuses -- in which he has performed well -- at the end of March, especially one in Washington state, where more than 100 delegates are at stake.
First up though, another round of voting
this weekend, with Democratic contests on Saturday in Kansas, Louisiana and Nebraska. Maine follows on Sunday.
Republicans will head to the polls in Kansas, Kentucky, Louisiana and Maine on Saturday. Puerto Rico votes on Sunday.