JERUSALEM (JTA) — Billionaire casino magnate Sheldon Adelson and his wife, Dr. Miriam Adelson, have pledged $13 million to Birthright Israel in recognition of its bar mitzvah year.

The money is earmarked to reduce the waiting list for participants. It comes on top of a $20 million challenge grant made by the Adelsons earlier this year.

In addition to the Adelson family’s gifts, the Birthright Israel Foundation campaign has raised $28 million for 2012.

“We are so grateful to the Adelsons for all they have done for us,” said Gidi Mark, CEO of Taglit-Birthright Israel. “This new gift brings their total giving to over $140 million and moves us significantly toward our target of 42,000 participants this year.”

The government of Israel provides matching grants to Birthright.

“When we discovered that 5,000 more young adults could still attend a trip this year if the funding was available, we felt compelled to act,” Sheldon Adelson said in a statement. “With over 20,000 young adults on the waiting list, we feel that reducing that list must be a top priority of the Jewish community. For those young adults still on the waiting list, we urge them to keep applying. We plan on continuing to do all we can to provide this opportunity to everyone who is interested.”

The Adelsons have been significant financial backers of Republican presidential candidates.