The Hall of Fame's board cut a player's eligibility from 15 years to 10, which gives McGwire a maximum of two more appearances on the writers' ballot. Bonds, Clemens and Sosa, shunned so far along with other Steroids Era stars, can be considered up to eight more times each by the Baseball Writers' Assn. of America.
Clemens, a seven-time Cy Young Award winner, dropped from 37.6% to 35.4 last year in his second ballot appearance, well short of the 75% needed for election. Bonds, a seven-time MVP and baseball's career home run leader, fell from 36.2% to 34.7.
McGwire dropped from 16.9% to 11, down from a peak of 25.6 in 2008. Sosa, who hit 609 homers, dropped from 12.5% to 7.2 — close to falling below the 5% threshold for remaining on the ballot.
This is only the second change in voting rules since 1985, when the 5% threshold for remaining on the ballot was instituted. In 1991, players on baseball's permanent ineligible list were barred from the ballot, a move that prevented career hits leader Pete Rose from being considered. Rose agreed to a lifetime ban in 1989 after an investigation by Major League Baseball concluded he bet on the Cincinnati Reds to win while managing the team.
Members of the BBWAA for 10 consecutive years at any point are eligible to vote. Under another change announced Saturday, eligible voters will be required to complete a registration form and sign a code of conduct, and their names will be made public, but not their individual votes.
Dan Le Batard, an ESPN host and Miami Herald columnist, was kicked out of the BBWAA for one year and barred from future Hall votes in January after he turned over his 2014 ballot to a website that allowed readers to choose the selections.