CINCINNATI — President Obama and his Democratic allies aren't waiting for Republican Mitt Romney to reveal his vice presidential choice. They're already scuffing up the likeliest picks.
In emails to donors and supporters, Mr. Obama's campaign is critiquing the Republican running mate favorites while urging home-state Democrats to chime in about their shortcomings.
The pre-emptive strikes reflect a sense that time is precious to sway opinion in a close presidential race dashing quickly toward November.
Mr. Obama's campaign has targeted New Jersey Gov. Chris Christie, former Minnesota Gov. Tim Pawlenty, Ohio Sen. Rob Portman and Sen. Marco Rubio of Florida. Independent groups sympathetic to Mr. Obama also are starting to unload their opposition research on the would-be vice presidents.
Mr. Romney's campaign criticized Mr. Obama for seeking critiques and called them little more than "negative smear campaigns."
New Obama ad questions Romney on income taxes
President Obama is launching a new ad that questions whether rival Mitt Romney paid any income taxes in the past.
The ad shows footage from a Romney interview with ABC News in which the Republican presidential candidate was asked if he had ever paid a lower tax rate than 13.9 percent. The narrator asks, "Did Romney pay 10 percent in taxes? Five percent? Zero?"
The ad is slated to air in Virginia, North Carolina, Florida and Ohio during the coming week, the same states where Mr. Romney is taking a bus tour beginning Saturday.
Obama allies, such as Senate Democratic Leader Harry Reid, have questioned whether Romney paid taxes in the past decade.
Mr. Romney has responded that he has paid taxes every year — and, he adds, "a lot of taxes."
Democratic candidates want citizenship bill part of platform
In an appeal to Latino voters, three Senate candidates in the Southwest are calling on delegates to the Democratic National Convention to make support of a bill to help young illegal immigrants gain citizenship a part of the party platform.
The Democratic nominee for a Senate seat from New Mexico, Rep. Martin Heinrich, is leading the effort. Mr. Heinrich says that formally supporting the immigration proposal would provide voters with a clear choice on an issue that many care deeply about.
Democratic candidate Shelley Berkley in Nevada says she supports the effort to get the Dream Act into the Democratic Party platform. A spokesman for Senate candidate Richard Carmona in Arizona says he does as well.
It's unclear whether the Democrats' platform committee will support the effort.
First lady stumps through pivotal Keystone State
PHILADELPHIA — Michelle Obama is exhorting grass-roots supporters to keep working hard for her husband's re-election
The first lady rallied hundreds of people Thursday at the University of the Sciences in Philadelphia, the first of three stops in the state. She says President Obama has fought to keep the American dream alive for the middle class.
She later plans to attend campaign events in suburban Fort Washington and farther north in Bethlehem.
Pennsylvania voted for Mr. Obama in 2008. The state, however, has a strict new voter identification law that critics say will disenfranchise likely Democratic supporters in November.
The law is being challenged in state court.
Jackson aide expects boss to return within weeks
CHICAGO — An aide to Rep. Jesse L. Jackson Jr. says the Illinois Democrat is expected back from medical leave within weeks.
Spokesman Rick Bryant said Thursday he recently spoke with Mr. Jackson and the congressman seemed upbeat and "like his old self." He says Mr. Jackson wanted him to call mayors to get updates on projects in his district that stretches south of Chicago.
Mr. Jackson has been on medical leave for two months. He's being treated for depression and gastrointestinal issues at Minnesota's Mayo Clinic.
His office has released few details. Staff initially said his leave that started June 10 was for exhaustion and later said it was for treatment of a "mood disorder."
His office only recently disclosed Mr. Jackson had been transferred to the Rochester clinic after spending time at an Arizona facility.
Livestock farmers seeking pause in ethanol production
Livestock farmers and ranchers seeing their feed costs soar because of the worst drought in decades are demanding that the Environmental Protection Agency waive production requirements for corn-based ethanol.
The Obama administration sees no need for a waiver, siding with corn growers — many of them in presidential election battleground states Iowa and Ohio — who continue to support the requirement.
The livestock industry argues that at a time when supplies are precarious, the large share of the corn crop going to ethanol production is driving up prices and driving them out of business.
The Renewable Fuel Standard, enacted in 2005 and then significantly expanded in 2007, requires that 13.2 billion gallons of corn starch-derived biofuel be produced in 2012.
Trade deficit falls, oil imports a factor
The U.S. trade deficit fell to its lowest level in 18 months in June, pushed down by a steep drop in oil imports and a rise in exports.
The trade gap narrowed to $42.9 billion in June, down from $48 billion in May, the Commerce Department said Thursday.
Exports rose 0.9 percent to a record high of $185 billion. Overseas sales of autos, pharmaceuticals and industrial machinery increased. Despite Europe's struggling economy, exports to the 27-nation European Union grew 1.7 percent.
Imports fell 1.5 percent to $227.9 billion, the lowest in four months. A key reason for the drop was the price of imported oil fell by the most in 31/2 years. That brought the trade deficit in oil to its lowest level since November 2010 and accounted for half of the improvement in the overall trade gap.
Excluding oil, the trade deficit dropped to $20.4 billion in June from $23.2 billion in May. Imports of computer equipment and TVs also declined.
A narrower trade gap acts as less of a drag on growth because it means the United States is spending less on foreign-made products and is taking in more from sales of U.S.-made goods.
The sharp drop in the deficit could mean the economy actually grew at a faster pace in the April-June quarter than first estimated. The government said last month that the economy expanded at a 1.5 percent annual rate in the second quarter. It will issue its second of three growth estimates later this month.
Economists are worried that slower overseas growth will reduce demand for U.S. exports. About one-fifth of U.S. exports go to Europe, which is in the third year of a financial crisis.
• From wire dispatches and staff reports