A Michigan voter casts a ballot at a polling station in Detroit on February 25, 2024.
CNN  — 

The Republican presidential primary season has been one long slog for the past month and half.

Just three states – Iowa, New Hampshire and South Carolina – have had caucuses or primaries in which both Donald Trump and Nikki Haley were on the ballot. The small number of nominating contests allowed the candidates to camp out and provide individual attention to each state.

Tuesday’s Michigan primary marks a major pivot away from that model. Neither candidate has been able to pay too much attention to the Wolverine State, which makes it a good testing ground for how the GOP primary process will unfold as the campaign becomes nationalized over the next three weeks.

This is likely very good news for the former president.

Trump is the massive favorite in Michigan. Recent polling has been limited, but he led Haley 72% to 27% among likely GOP primary voters in a CNN/SSRS poll conducted at the end of last year. That lead was larger than his advantage in any of the final surveys leading up to the aforementioned three early nominating contests this primary season.

Now, Haley was able to close the gap with Trump in New Hampshire and South Carolina after polls had previously shown her well behind. Even three weeks out from the Palmetto State primary, polls had Haley down by 35 points, but she lost by 20 points after weeks of campaigning.

Haley, though, doesn’t have the luxury of time in Michigan. The primary is here and now. Only in the past week did she announce a state leadership team and start airing television ads and holding campaign stops in the state.

If Trump’s Michigan support hasn’t budged significantly since December, the polling would then look a lot like what we see nationally. This is the first state on the primary calendar where Trump is above 70% in the polls, which is also where he is in national surveys of the Republican primary.

Haley’s inability to stake out time in Michigan is understandable given that it’s taking place a mere three days after the South Carolina primary.

The problem for her is that’s what the rest of the calendar looks like. We’re about to enter a stretch of the campaign that goes national very quickly, and you can’t devote a lot of time to any one state.

Just 6% of delegates have been allocated in the GOP primary so far. After Super Tuesday on March 5, about 50% of delegates will have been allotted. This will jump to about 56% two weeks from now and about 71% three weeks from now. That is, more than two-thirds of all GOP delegates will be assigned in the next three weeks.

What’s worse for Haley is the way delegates are allocated in most of the upcoming states. Instead of contests being strictly proportional (e.g., 25% of the vote nets you 25% of the delegates) as it is on the Democratic side and in Iowa and New Hampshire on the Republican side, most of the upcoming contests will be “winner take most” or “winner take all” in some fashion.

If Trump is able to win by any significant margin, he’ll pick up most, if not all, of the delegates in these states. You already saw this in South Carolina on Saturday. Trump won about 60% of the vote and 94% of the delegates.

Trump will, therefore, accrue a lot of delegates very quickly if the polling is to be believed. He’s up by somewhere around 60 points over Haley in recent national polls of the Republican primary from Marquette University Law School and Quinnipiac University.

Consider recent data from California and Texas to see how this is playing out on the state level.  These are the biggest delegate prizes on the GOP side on Super Tuesday. Both states have primary rules that will allow the winner to walk away with either most (or all, in the case of California) of the state’s delegates.

Trump leads Haley by about 40 points and 70 points in the most recent California and Texas polling, respectively.

If the polling holds, it’s possible that Trump will have a majority of delegates by March 12. There’s an even better chance he’ll hit that mark by March 19.

Haley, in other words, will have to rapidly change what’s expected to be a terrible national environment for her as the GOP primary barrels ahead. If she doesn’t, Michigan will mark the beginning of the end of her campaign.