Roy Halladay, Todd Helton, Andy Pettitte, Mariano Rivera
Martinez, Clemens, Bonds, Mussina, Schilling
Most Likely To Be Elected
While it will have taken Hoffman three ballots to gain enshrinement, Rivera will have no trouble getting into the Hall of Fame on the first try. Between his all-time saves record, his incredible postseason performance (0.70 ERA in 141 innings) in helping the Yankees win five World Series championships, his substantial edge on every other reliever besides Dennis Eckersley in WAR and JAWS and his status as one of the game's beloved ambassadors, a share in the 90–95% range seems quite likely. With all ballots public by this point, there's an outside shot he could be the first unanimous pick in Hall history, though the chance of a look-at-me vote is always possible.
Halladay, a two-time Cy Young winner with a 131 ERA+, tops the average enshrined starter's seven-year peak but is a bit short on the career and JAWS fronts, ranking 42nd overall in part because he wasn't a strikeout pitcher and didn't accrue value as quickly. With "only" 203 wins and 2,117 strikeouts and no World Series experience, his resumé will look short next to those of Schilling and Mussina, even with the hardware and the second no-hitter in postseason history. Thus, I'd expect Halladay to debut in the 40–50% range, enough to set him on an eventual path to election.
I don't expect the same for Pettitte despite his 256 wins and five rings. While his 117 ERA+ is in the vicinity of Hall of Famers Bert Blyeven, Steve Carlton, Fergie Jenkins, Gaylord Perry and Phil Niekro, he lacked their staying power (all of those guys had at least 1,000 more innings, some of them even 2,000 more) or their Cy Youngs. Pettitte is just 88th in JAWS, and even as his Mitchell Report mention and admitted use of human growth hormone recede further into the distance, it's not going away entirely, and neither are the other pitchers on the ballot who stack up better. I'd expect a share of around 30%, which will keep people talking about him.
Helton, whose peak is above the first base standard and who's within one point of the JAWS standard, will have his adherents, but between his mid-career falloff and the voters' resistance to Coors-inflated stats—ask Larry Walker about that—he's in for rough sledding.
With no other first-ballot candidate besides Rivera getting in the way, this is the opening that Martinez, who will be in his final year of eligibility, needs to get his long-overdue plaque. Bonds and Clemens will move into the mid-to-high 60s, with Mussina well into the 60s and Schilling into the high 50s. Walker (in his ninth year) or Manny Ramirez (despite the two positive tests) will be in position to gain some ground, and McGriff (in his tenth and final year) could get a sendoff in the 30s or 40s, which would still be a much higher share of the vote than he's ever seen.