Legislation to grant the District a full vote in Congress for the first time likely would be enacted.
Democratic presidential nominee Sen. Barack Obama and Republican opponent Sen. John McCain split along traditional party lines on the issue, but those lines have been blurred by growing Republican support for a D.C. House seat.
A significant number of Republicans in Congress supported a D.C. voting rights bill last year, but the measure lacked the 60 Senate votes needed to move forward.
Those votes might be in reach if Democrats substantially increase their congressional majority in Tuesday’s vote as expected.
“I think Democrats are more likely to give it, because it’s a Democratic seat,” said Rep. Thomas M. Davis III, Virginia Republican and D.C. voting rights advocate who said he expects legislation granting the privilege to be passed soon.
Republicans have long blocked the District’s efforts for full representation in the House, citing constitutional concerns as well as the fact that it would add a reliably Democratic seat to Congress.
The District is now represented by a single nonvoting delegate - currently, Delegate Eleanor Holmes Norton, a Democrat. Her office carries a full vote in committee, but not on the House floor. The nonvoting delegate position was reinstated in 1970, a century after it was created, according to a timeline on the Web site of advocacy group D.C. Vote. The position had been eliminated in 1874 after a local presidential appointee grossly misspent federal funds.
Mr. McCain, in a statement to The Washington Times, said the Constitution only allows for states to have representation in the House. D.C. residents cannot gain such representation unless the Constitution is amended or portions of the city are ceded to Maryland, he said.
“I do not support legislation to give the District a vote in Congress because I believe that such a law would be unconstitutional,” Mr. McCain said.
Mr. Obama, meanwhile, earned the endorsement of D.C. Mayor Adrian M. Fenty in this year’s Democratic primary, partly because of the senator’s pledge to support the District’s quest for congressional representation.
“Those who live in our nation’s capital pay taxes like other Americans and serve bravely in the armed forces like other Americans. Yet they are not afforded a vote in Congress,” Mr. Obama said last year. “The right to vote belongs to every American, regardless of race, creed, gender or geography.”
A compromise proposed last year by Mrs. Norton and Mr. Davis, who is retiring, cleared the House with more than 20 Republican votes. A similar effort died in the Senate after a procedural measure failed to win 60 votes.
The bill would have granted the District a seat in the House while adding a fourth House seat for Utah, which is largely Republican.
Forty-seven Senate Democrats - including Mr. Obama, who co-sponsored the measure, and his running mate, Sen. Joseph R. Biden Jr. of Delaware - eight Republicans and two independents voted in favor of advancing the measure in September 2007. Mr. McCain voted against it.
Mr. McCain’s stance presents a conundrum for D.C. Republicans who support representation.
The D.C. Republican Committee backs a House seat for the District, but also supports Mr. McCain.
But Paul D. Craney, executive director of the committee, said Mr. McCain is approachable and might be amenable to changing his position.
Mr. McCain has close ties to Sen. Joe Lieberman of Connecticut, an independent who sponsored the Senate measure last year.
“He’s the type of candidate you can come to with the D.C. voting rights issue, and there’s a good possibility he could change his mind on it,” Mr. Craney said.
Still, Ilir Zherka, executive director of D.C. Vote, said an Obama administration spells certain success for his group’s cause.
“The big question for us is right now, ‘What happens if the bill gets to the White House?’ ” Mr. Zherka said. “With a President Obama, that bill gets signed. With a President McCain, then it’s an open question.”