President Barack Obama told donors in Maryland on Monday that this November's midterm election will be "critical" if Democrats hope to increase the federal minimum wage or approve major changes to U.S. immigration laws during his final years in office.

Speaking at a fundraiser held at the home of a Potomac physician, the president argued that Republicans in the House of Representatives have become caught in an "endless loop" over issues such as the health care law and the 2012 attack in Benghazi, Libya, that killed four Americans.

Democrats are attempting to hold their ground in what many believe will be a difficult midterm election for the president's party. Independent political analysts are predicting Republicans will either maintain or expand their current majority in the House.

Obama was making his fifth appearance this year for the Democratic Congressional Campaign Committee, charged with electing Democrats in competitive House districts. Gov. Martin O'Malley, Rep. Steny Hoyer of Southern Maryland, Baltimore Rep. Elijah E. Cummings and other prominent state Democrats also attended the fundraiser.

The event was held at the home of Dr. Jeff Drezner, founder of Clinical Care Options, a company that provides continuing education for health care professionals. He and his wife, Lora, donated tens of thousands of dollars to Democratic candidates and organizations ahead of the 2012 election.

Under a white tent on the lawn of the couple's home, Drezner told about 65 attendees that the controversial Affordable Care Act had been a "wild success."

The House Democratic campaign arm raised $7.1 million last month and has more than $43 million in the bank. Its Republican counterpart, the National Republican Congressional Committee, has not yet reported its numbers.

"It's no surprise that President Obama is doing everything in his power to finish his presidency the way he started it — with Nancy Pelosi as speaker of the House," NRCC spokesman Ian Prior said in a statement. That partnership, he said, "is the only way he can complete his disastrous agenda."

The Drezners held a fundraiser in 2011 for Rep. Chris Van Hollen, a Maryland Democrat and a past chairman of the House Democratic campaign group. Van Hollen was also expected to attend the fundraiser Monday, which was billed as an "intimate dinner" with the president, Pelosi and others.

Tickets cost between $10,000 and $32,400, according to an invitation obtained by the Sunlight Foundation.

Despite the difficult position in which Democrats find themselves nationally, party incumbents in Maryland all appear to be in strong position for re-election in November.

Republicans hold a 233-199 advantage in the House.

Democrats in Washington, including Obama, have been pressing for months to raise the federal minimum wage to $10.10 but have met resistance from Republicans, who say they are concerned about the impact such a move could have on the economy.

The two parties have also been at odds over how to address the nation's immigration system, which all sides agree is broken.

john.fritze@baltsun.com

twitter.com/jfritze