ST. LOUIS, Missouri (CNN) - Gone are the town hall-style meetings filled with 200 people.
Gone are the days where simply showing up to an event meant there was a good chance that if you wanted to meet the candidate, you could.
That may have been the way it was in Iowa, but this - pardon the slang - ain't Iowa. It's now the lead-up to February 5, the 22-state mega contest known as Super Tuesday.
For Obama, it means criss-crossing the country, dropping in on cities he's never campaigned in-some of them in states he's never even been to-for what is sometimes one event per state.
But these aren't your average gatherings. Unless you consider an indoor football arena filled with what can be tens of thousands of people your "average gathering."
Today's Obama "rallies" - the term used in lieu of "town hall meetings," which, most of the time, means Obama won't take audience questions - now look more like rock concerts than anything else.
His staff has made it a goal to pack arenas that seat thousands as tight as they possibly can. People in overflow crowds have been overheard saying the campaign warned them that tickets would be granted to more people than there will be room for.
But after the event ends, it's not uncommon to hear staffers mention how "surprised" they were that so many people showed up. And they may, in fact, be legitimately surprised. Still, when the press arrived at the event at the Taco Bell Arena on the campus of Boise State University in Boise, Idaho, Saturday morning, a giant black curtain was hanging and dividing the seating area, keeping about a quarter of the seats out of view. It's a tactic sometimes used by campaigns - including rival Hillary Clinton's - that shrinks the amount of seating space in a room and gives an illusion there are more people than there actually are.
To his credit, Obama rarely partitions a room like that. A campaign spokeswoman said they had done it on at least one other occasion - a canvass kickoff rally back in the day in Des Moines - in order to, as she said, better "frame the shot" for cameras.
Soon, though, the curtain at the Boise event slowly came down, revealing vacant chairs and a number of large hand-painted campaign banners. A crowd that had still been waiting outside was beginning to fill these seats.
Arena officials estimated 15,000 showed up, setting a new record for number of people ever inside the building.
But the curtain illusion is a rarity in this campaign. There's no denying his crowds have been simply monstrous.
According to the campaign, Obama's Wednesday stop in Denver, Colorado, saw 9,500 fill an indoor arena and an additional 9,000 couldn't get in filled an overflow room and an outdoor lacrosse field. (It's worth noting, however, that this number could not be verified since members of the traveling media were not allowed outside to witness this.)
An event in an arena in St. Louis, Missouri, on Saturday, saw, according to the campaign, 20,000 people.
These kinds of numbers are, to say the least, difficult to confirm, but in general they appear believable, and this type of arena-style venue seems to have become the norm, at least in the days before Super Tuesday.
Obama communications director Robert Gibbs said a large venue benefits them particularly in states holding caucus-style nominating contests as opposed to primaries, i.e. New Mexico, Idaho, and Minnesota-three states the Illinois senator made stops in on Friday and Saturday.
"Theres a big organizing function to doing a large event in a caucus state because it gives you access to names," Gibbs said. "It helps you direct people to the polling places, it gives you the ability to recruit election day volunteers, it helps you honestly just get the vote out for Tuesday."
–CNN Political Producer Chris Welch