Luck is the only repeat finalist this season, while Griffin is the first Baylor player to get an invite to the ceremony. The school that never has had a player finish better than fourth in the Heisman voting now seems to have the front-runner.
Mathieu, the LSU defensive back nicknamed "Honey Badger," has made numerous game-changing plays for the top-ranked Tigers.
The field was deep this season and several deserving players didn't make the cut. Boise State quarterback Kellen Moore, a finalist last season; Southern California quarterback Matt Barkley; and record-breaking passer Case Keenum of Houston did not receive enough votes to be among the final five.
Ballots from the 926 voters, mostly media members and former winners, were due Monday evening.
Luck was the Heisman runner-up to Auburn's Cam Newton last year and passed up a chance to be the No. 1 pick in the NFL draft to return to Stanford for his junior season. From the moment he made the decision to stay in school in January, he became the odds-on favorite to win the big bronze statue.
Luck is looking to become Stanford's second Heisman winner, joining quarterback Jim Plunkett, who won in 1970.
"It would mean a lot," Luck said in an interview on ESPN. "I would mean a great deal for the university. Mean a lot to me and a great deal to the football program, as well."
He had another stellar season, passing for 3,170 yards with 35 touchdowns while leading the Cardinal to an 11-1 record and a second straight BCS bid. But the competition has been fierce and numerous contenders emerged.
The prognosticators now have Griffin as the most likely winner.
Heismanpundit.com, which has successfully predicted the past four winners with a straw poll of 13 voters, had Griffin as its top vote-getter on Monday. Luck was second and Richardson third.
Stiffarmtrophy.com, which compiles ballots from voters who make their choices public and has predicted the past nine winners, had Griffin winning by a comfortable margin over Luck, with Richardson third.
Griffin leads the nation in passer rating (192.3), with 3,998 yards and 36 touchdowns. He has also run for 644 yards and nine touchdowns. And much like Luck, Griffin has led a long-struggling program to its greatest success in decades. Baylor is 9-3 this season, its first nine-win season since 1986, including its first victory against Oklahoma.
"Baylor nation we're in there," Griffin said. "Now we just got to try to snatch it. Hopefully the vote turns out our way.
"Being invited is an honor. It's not all that we want, but it's a starting spot."
The best showing a Baylor player has had in the Heisman voting was quarterback Don Trull's fourth-place finish in 1963.
Richardson has been the unquestioned offensive engine for No. 2 Alabama. He's fifth in the nation in rushing at 131.9 yards per game and tied for fifth in touchdowns with 23. Richardson and the Crimson Tide will meet Mathieu and LSU in the BCS championship game on Jan. 9 in New Orleans.
Mathieu, though, is more like Charles Woodson, the do-it-all defensive back who won the 1997 Heisman for Michigan.
Mathieu has forced five fumbles, intercepted two passes and scored four touchdowns, including two long punt returns in LSU's past two games against Arkansas and Georgia.
He also was suspended for a game this season for violating the team's drug policy.
Ball has been a touchdown machine for Wisconsin and ranks fourth in rushing at 135.3 yards per game. He has 12 more touchdowns than the next best player in the nation and if he can tack on two more in the Rose Bowl against Oregon, he'll break Sanders' record.