Clemens was acquitted this summer in federal court on six counts that he lied and obstructed Congress when he denied using performance-enhancing drugs.
Bonds was found guilty in 2011 by a federal court jury on one count of obstruction of justice, ruling he gave an evasive answer in 2003 to a grand jury looking into the distribution of illegal steroids. Bonds is appealing the verdict.
McGwire is 10th on the career home run list with 583, but has never received even 24 percent in his six Hall tries. Big Mac has admitted to using steroids and human growth hormone.
Palmeiro is among only four players with 500 homers and 3,000 hits, yet has gotten a high of just 12.6 percent in his two years on the ballot. He drew a 10-day suspension in 2005 after a positive test for PEDs, and said the result was due to a vitamin vial given to him by teammate Miguel Tejada.
Biggio topped the 3,000-hit mark — which always has been considered an automatic credential for Cooperstown — and spent his entire career with the Houston Astros.
"Hopefully, the writers feel strongly that they liked what they saw, and we'll see what happens," Biggio said last week.
Schilling was 216-146 and won three World Series championships, including his "bloody sock" performance for the Boston Red Sox in 2004.
AP Baseball Writer Janie McCauley and AP Sports Writers Arnie Stapleton and Dave Skretta contributed to this report.
Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.