Opening a significant lead in the money primary, Illinois Sen. Barack Obama raised $32.5 million in the second quarter of 2007, eclips-ing New York Sen. Hillary Rodham Clinton and other rivals for the Democratic presidential nomination.

Obama became the first Democrat to surpass $30 million in a quarter during a nonelection year, a feat his campaign said was accomplished not just with help from wealthy, traditional donors but also with a strong showing among small contributors.

The Illinois senator, who was born in Hawai'i, trails Clinton in most polls, but the favorable performance reported yesterday is expected to increase the pressure on Clinton's team.

Clinton's aides announced earlier that she had raised $27 million in the second quarter of 2007. Her total would have set a record among Democratic presidential candidates for the same period in past campaigns.

The $32.5 million that Obama amassed is more than the $30.8 million raised by all other Democratic presidential candidates for the same period four years ago and nearly matches the $35 million that President Bush raised in the second quarter of 2003.

In a statement issued yesterday, Obama said 154,000 donors had given to his campaign in the second quarter.

"Together, we have built the largest grass-roots campaign in history for this stage of a presidential race," Obama said, adding that his backers seek "healthcare for all, energy independence and an end to this war in Iraq."

Obama and the other candidates have until July 15 to file their full campaign finance reports detailing the exact amounts they raised in the second quarter of 2007 and identifying their donors. The quarter ended Saturday.

Republican presidential candidates are expected to release their summaries this week.

The Los Angeles Times and Washington Post contributed to this report.