The Atlantic Coast Conference entered the season flexing its muscles with the defending national champions, the reigning Heisman Trophy winner and abundant hope to show it's deeper than just one team.

Halfway through the season, it hasn't turned out that way.

The ACC seems to be a league with one dominant team in the Clemson Tigers and several solid squads still learning how to contend on the national stage.

Florida State's vast array of talent made them the trendy preseason pick to supplant Clemson while Louisville and Heisman winner Lamar Jackson appeared ready to challenge for league supremacy.

But the Seminoles and Cardinals have come up short.

Florida State is off to its first 1-3 start in 41 years in big part to losing quarterback Deondre Francois for the season in its opener with Alabama. Louisville was waylaid at home, 47-21, by Clemson in a September showdown that fizzled out before halftime. Virginia Tech, which won the ACC Coastal Division a year ago, also had its chance against Clemson at home and it, too, came up short in a 31-17 loss.

Now, a new group of contenders have emerged — all with questions about their staying power.

"We can never rest easy or think we've at the top," Clemson defensive end Austin Bryant said. "There will be challenges every week."

The ACC teams with the best chance of beating Clemson and earning a spot in the College Football Playoff along with the Tigers are No 11 Miami and No. 20 North Carolina State.

The Wolfpack is off to their best start since Philip Rivers was the quarterback 15 years ago. The Wolfpack, with wins over Florida State and Louisville, had Clemson in its sites a year ago but a blocked field at the end of regulation bailed out the Tigers, who won 24-17 in overtime.

North Carolina State hosts the Tigers on Nov. 4 with the ACC Atlantic clearly in play.

"We've put ourselves in a great place, but that doesn't mean we're satisfied at all," Wolfpack coach Dave Doeren said. "Got a great focus on where we want to go."

Mark Richt has Miami riding high — and leading the Coastal Division — after a late victory over the Seminoles last week, its first rivalry win in eight years. The Hurricanes are tied at the top by another surprise team, Georgia Tech.

Miami's only shot at Clemson would come in a potential ACC championship matchup. Georgia Tech plays at Death Valley on Oct. 28

It may not be the way the ACC drew it up this summer, but CBS Sports college football analyst Rick Neuheisel believes the league has plenty of reasons to smile.

It's got the powerhouse program gaining the headlines — "Everytime you go to ESPN's website, we're on the front page," Tigers' Bryant says — along with increased depth throughout both its divisions.

"If I'm (ACC commissioner) John Swofford, I'd be smiling right now," Neuheisel said.

The league would like those improvements to translate into regular runs at the College Football Playoff.

And that, Pitt coach Pat Narduzzi says, takes time for coaches to recruit — and patience from administrators to weather the quick calls from fans for change when problems arise.

Narduzzi said when a coach like Doeren is given time at North Carolina State, "the program is very, very stable at this point."

Current stability does not guarantee future success, North Carolina coach Larry Fedora said. His Tar Heels were 8-0 in the ACC two years ago and took Clemson to the wire, 45-37 in that season's league title game and looked like a league contender for years to come. But North Carolina has gone 9-10 the past two seasons, including a 1-5 start to 2017.

"The thing is there's never a time where you can relax," Fedora said of trying to maintain momentum as a program. "You're constantly dealing with issues all the time, and so there's a lot of variables involved. And you've got to stay on top of every single one of them all the time to be able to play at a certain level."

Neuheisel, who coached at Colorado, Washington and UCLA, sees ACC schools using increased revenue from its TV contracts to hire talented coaches like Justin Fuente at Virginia Tech and Bronco Mendenhall at Virginia and update facilities, like Clemson's recently opened, $55 million football building complete with a slide and a bowling alley.

It's similar to the SEC where Florida and LSU won national titles in the mid-2000s, other programs like Alabama and Auburn wanted a piece of the pie, he said. Schools are saying, "we now are starting to enjoy the riches that come from this television bonanza, let's start investing in our programs."

"It's a bunch of programs that are seeing that, hey, there's reason to do this," Neuheisel said.

AP Sports Writers Aaron Beard in Chapel Hill, North Carolina; Will Graves in Pittsburgh; John Kekis in Syracuse, New York; Hank Kurz in Charlottesville, Virginia; and Joedy McCreary in Raleigh, North Carolina contributed to this report.