The Republican candidates are marching into Boulder to go head-to-head in their next debate at the Coors Event Center on the University of Colorado campus. Here's what you need to know:
When will the debate happen?
Two debates are actually scheduled Wednesday. The first happens at 6 p.m. EST and will feature candidates who didn't place in the top 10 in recent national polls. The main event happens at 8 p.m. EST
After some tension with candidates, CNBC agreed to a two-hour debate, including commercial breaks.
Can you go?
Basically, no. While there are 11,000 seats in the Coors Events Center, almost all of those seats will be empty.
The RNC and CNBC originally made 50 tickets available to the university, which includes faculty and students. Now 150 are available but they're going to students, faculty and some guests.
Who will be participating?
Businessman Donald Trump will be front and center at the 6 p.m. debate alongside Ben Carson, a retired neurosurgeon. Both are leading in national polls.
Other participants include Florida Sen. Marco Rubio, former technology executive Carly Fiorina, former Florida Gov. Jeb Bush, Texas Sen. Ted Cruz, former Arkansas Gov. Mike Huckabee, New Jersey Gov. Chris Christie, Ohio Gov. John Kasich and Kentucky Sen. Rand Paul.
Rick Santorum, Bobby Jindal, George Pataki and Lindsey Graham face off in the 4 p.m. round.
Which candidate is currently in the lead?
According to the latest big poll from CBS and The New York Times, Carson has surpassed Trump; 26 percent of voters favor Carson compared to Trump's 22 percent. However, Trump is still slated to appear in the center. The rest of the candidates are far behind.
Who is hosting the debate?
This is a CNBC debate so CNBC Anchors Carl Quintanilla, Becky Quick and John Harwood will moderate.
What is the subject of the debate?
CNBC says they'll focus on the economy -- with factors like job growth, taxes and retirement, as well as technology. CNBC has published articles this week about how the candidates feel about marijuana; it's likely the topic will arise.
The next Republican debate happens Nov. 10 in Milwaukee. Fox Business Network will host with the Wall Street Journal.