Of all the players who are eligible, the only one not in the Hall is Norm Cash. Now it might seem like his 1961 season when he batted .361, hit 41 HRs, drew 132 walks had a .487 OBP and a .662 SLG was the flukiest season ever. He never batted .300 again (his last year was 1974) nor did he ever reach 40 HRs or 100 RBIs. He never reached a .400 OBP again or a .600 SLG (he only reached .500 3 more times-he was pretty much a full-time player until 1973).
But his 1961 season was not the flukiest. I have written about this before. See Which Players Had The Most Uncharacteristically Good Seasons? Cash had the 25th flukiest season.
It will be interesting to see what happens with the voting for some of these other guys. Bonds, Giambi, Sosa and AROD might be penalized by some voters for using PEDs. Pujols should get in easily. It is probably too early to tell for Kemp. But Beltre is interesting. His yearly performance has been inconsistent. But he now has 47.6 WAR and he will be 33 starting next year. He is 189th in career WAR among position players but if he could get up to about 62, he would be in the top 100. His last two years were 6.1 and 5.2, so another 14.4 seems possible. Being in the top 100 would make him a legitimate candidate.
Now a WAR of 10 gives an edge to guys who played after 1961, when the season went to 162 games (in the AL, 1962 in the NL). So I looked for guys who had 9.5 or more before then (covering about the 5% difference in games from a 154 game season). There were a total of 82 seasons of WAR ≥ 10 and another 21 ≥ 9.5 before the 162 game season came in. Of the guys in that group who are not in the Hall of Fame we have George Stone (9.8, 1906), Joe Jackson (9.5, 1912), and Al Rosen (9.7, 1953, the year he missed the triple crown by losing the batting title to Mickey Vernon, .337-.336).
Click here to see George Stone's stats at Baseball Reference. He did not have a long career, ending at 33 with 3600 PAs. His next highest WAR was 5.2. Click here to read his SABR bio by John McMurray. This passage discusses his decline:
"After his great initial success, Stone held out for $5,000 to start the 1907 campaign. In order to make sure that team owner Robert Hedges met his demands, Stone did not report to the team until right before the start of the season. The holdout, as one publication put it, "seems to have been the turning point of his career." On one level, "the papers aired the case and naturally by some Stone was censured for what was termed unreasonable demands." Moreover, "when he was finally granted the amount he asked, the fans figured that a player getting such big money should never fail to deliver the goods. Any time Stone failed, and unfortunately for him he had a rather tough year in 1908, he was roasted to a turn by the fans. Stone began to show signs of slowing up that year."
Stone's statistics fell off in both 1907 and 1908, though he was still an outstanding hitter. One account indicates that he contracted malaria in 1908, and Stone's production plummeted in 1909 when he suffered an injury to his ankle. That injury cost Stone his speed, which had enabled him to beat out many infield hits. He also had problems with his arm, and "any time a ball was hit into his territory the opposing base runners advanced almost at will. The worry over all these things caused Stone's batting to suffer and as a result the sensation of the American League of 1906 was a near joke in 1910." Stone never hit higher than .300 after 1907, and his average fell to .256 in 1910, his last season in the major leagues. Stone returned to the Milwaukee Brewers in 1911, batting .282, but injuries led him to retire from professional baseball just 12 games into the 1912 campaign."