Donald Trump heads to Georgia in first visit after South Carolina sweep

Republican frontrunner Donald Trump heads to Georgia Sunday after a dominating victory in South Carolina's primary that cemented his position as the candidate to beat in the GOP primary and forced his bitter rival Jeb Bush to abandon the race.

Trump makes Georgia his first stop after besting a crowded field that included Florida Sen. Marco Rubio, Texas Sen. Ted Cruz and Ohio Gov. John Kasich. Expect a raucous event: He rented out an exhibit hall at the Georgia World Congress Center that seats 10,000.

The next Republican contest will be held Tuesday in Nevada, but the March 1 vote that features Georgia and a sweep of other Southern states could be the defining moment of the campaign. That's when a quarter of the delegates needed to secure the nomination are up for grabs - and could be the last chance for establishment Republicans to rally behind a mainstream candidate.

Larry Sabato, the University of Virginia political scientist, put it this way:

Let's make no mistake: Trump, amazingly, is in a commanding position to become the Republican presidential nominee. The fact that he won about the same share of the vote in New Hampshire and South Carolina -- two wildly different states -- shows the broad appeal of his campaign among a significant portion of the Republican electorate.

As we noted in the Crystal Ball on Thursday, we're rapidly approaching a critical point in the Republican primary process: After Florida, Illinois, Missouri, North Carolina, and Ohio vote on March 15, nearly 60% of the Republican delegates will have been won. If someone is going to beat Trump, Rubio probably has the best shot, but the hour is growing late for all of the non-Trump candidates.