Congressman Gerald Connolly gives the thumbs up sign after voting at Kena Temple in Fairfax on Nov. 2, 2010. (Photo by Gerald Martineau for The Washington Post)

In a letter to McDonnell (R) and legislators Wednesday, the Northern Virginia Democrat said the state would lose more than $9.2 billion in federal money over the first five years of the new health-care law if it doesn’t participate in the expansion.

“It is time to put policy decisions ahead of political posturing for the good of the commonwealth and its citizens,” Connolly said.

On Tuesday, McDonnell told legislators he was considering joining six other Republican governors in opting out. “A great expansion of Medicaid, without significant reform of the so-called ‘federal-state partnership,’ is not responsible,’’ he wrote in a letter Tuesday.

 But Connolly said the state’s refusal to be in the program would deny health insurance coverage to a quarter-million Virginians, forcing them to seek costly primary medical care at expensive hospital emergency rooms.

He said the first three years would be funded by the federal government and even after that the state’s share would never exceed 10 percent of the expansion cost. The state stands to receive $17 in federal funds for every state dollar it spends on its Medicaid expansion program.

“While it appears Virginia now has the ability to reject these federal funds, I am sure you will agree that doing so would be an historic mistake for our commonwealth,’’ he wrote.

According to the Kaiser Family Foundation, 245,840 uninsured Virginians would likely receive Medicaid coverage under the expansion. 

Republican presidential candidate Mitt Romney speaks to Virginia Gov. Bob McDonnell (L) at an election rally in Sterling last month. (JASON REED/REUTERS)

McDonnell, chairman of the Republican Governors Association, has sent a letter on behalf of Republican governors to President Obama seeking information, but he has said that he hopes a new Congress and president will repeal the law that he considers a massive unfunded mandate.

A McDonnell spokesman was not moved by Connolly’s plea.

“We appreciate this predictable letter from Mr. Connolly,’’ Tucker Martin said. “I’m sure he joins many of his colleagues who are running the same political play in their respective states. If Mr. Connolly is actually interested in policy, and not just politics, we encourage him to find a copy of the substantive, detailed letter the Governor sent to the President yesterday that highlights the numerous policy issues that must be addressed before states can accurately determine their most responsible and prudent course of action on this issue.

“As Mr. Connolly knows, Medicaid spending has increased by 1600 percent in Virginia over the past three decades, and it has gone from accounting for 5 percent to now 19 percent of the state budget,” Martin continued. “The program, as currently constructed, is a budget buster, and absent major reforms Virginians can’t afford an expansion in the years ahead. But again, Mr. Connolly knows that. You have to love campaign years.”