BLOOMBERG TO INTRODUCE McCAIN IN BROOKLYN TODAY

First, Senator Obama, now Senator McCain. Mayor Bloomberg will introduce the presumptive Republican nominee today when he holds a campaign forum with small business leaders in Brooklyn. The joint appearance comes two weeks after Mr. Bloomberg introduced Mr. Obama before the Illinois senator’s speech on the economy at Cooper Union. Even though he is not running for president, the mayor has let it be known that his endorsement is up for grabs. Mr. Bloomberg is friendly with all three remaining candidates, but he has criticized the contenders as a group for a lack of specificity on policy matters dear to him, such as climate change and education. Mr. McCain’s small business roundtable at the Windows We Are company will be his first non-fund-raising appearance in New York since he wrapped up the Republican nomination battle last month. He has pledged to compete in traditionally Democratic states, although he is given virtually no chance of carrying New York come November.

CLINTON RADIO AD CRITICIZES OBAMA ON CAMPAIGN CLAIMS, ENERGY VOTE

Senator Clinton is running a radio ad in Pennsylvania that assails Senator Obama for what her campaign says are misleading statements about his record. The 60-second spot ridicules Mr. Obama for boasting that he does not take money from oil companies. What the Illinois senator does not tell voters, the ad says, is that campaign contributions from oil companies have been illegal for more than a century. The ad also contrasts Mrs. Clinton’s opposition to, and Mr. Obama’s support for, an energy bill pushed by the Bush administration that she says was a windfall for corporations. “It’s time for a president who takes on the oil companies in real life, not just on TV,” the narrator in the ad says.

OBAMA PREVIEWS ARGUMENT AGAINST PUBLIC FINANCING

Senator Obama is offering a preview of the argument he may use if he goes back on a pledge to accept public financing for the general election. The argument invokes the unprecedented financial support he has received from more than 1 million donors nationwide as a kind of public financing in its own right. “We have created a parallel public financing system where the American people decide if they want to support a campaign they can get on the Internet and finance it, and they will have as much access and influence over the course and direction of our campaign that has traditionally been reserved for the wealthy and the powerful,” Mr. Obama said at a fund-raiser in Washington, according to ABC News. The Illinois senator has raised record amounts of cash during the primary campaign and would likely be severely hampered by the spending limits associated with accepting public financing. He said in a questionnaire last fall that he would participate in the taxpayer-funded system if the Republican nominee did, but his campaign has suggested that was not a hard-and-fast pledge. The presumptive Republican nominee, Senator McCain, has struggled to raise comparable funds and has indicated he will take public financing in the general election. His campaign has already sharply criticized Mr. Obama for hedging on his pledge.

AMERICAN POSTAL WORKERS UNION ENDORSES OBAMA

The union representing 300,000 postal workers is endorsing Senator Obama, citing his pledge to take on special interests as president. The backing of the American Postal Workers Union boosts Mr. Obama’s already strong advantage over Senator Clinton among labor groups. He has previously been endorsed by the International Brotherhood of Teamsters and the Service Employees International Union, among others.

CLINTON CITES DIFFERENCES WITH HUSBAND

Senator Clinton has a long record of differing with President Clinton on trade policies, she told reporters outside Pittsburgh yesterday, the Associated Press reported. “I have a long record of being on a different attitude toward trade than my husband does,” she said. “I don’t think any married couple I know agrees on everything. And we disagree on this.” Mrs. Clinton opposes the Colombia free trade agreement proposed by President Bush, while Mr. Clinton supports it.