A bipartisan Senate group has agreed on a sweeping legislative proposal that would represent the most ambitious overhaul of the U.S. immigration system in three decades. The Washington Post will be examining portions of the bill on Post Politics in a series of blog entries.

Gay-rights advocates expressed disappointment Tuesday that the Senate group proposal did not include a new category of visas for same-sex foreign national spouses of U.S. citizens, who are not able to apply for such visas under current laws.