When supporters of the District of Columbia House Voting Rights Act celebrated its passage in the House on Thursday afternoon, they tried to come up with an analogy for what lies ahead.

Did they just wrap up the first quarter, as some said? Or are they now rounding second base? Perhaps Rep. Tom Davis (R-Va.), who crafted the legislation, put it best: “We understand we have two mountains to climb.”

Those mountains are the Senate and the White House, a pair of government entities whose support of the bill cannot be called enthusiastic.

White House aides have said they would recommend President Bush veto the bill if it reaches his desk. But that can happen only if the legislation makes it out of the Senate, where support remains tepid.

Of the 48 Senate offices that responded to a Roll Call telephone survey last week, 14 said they have not yet taken a position on the issue or did not know how they would eventually vote. Twenty-three said they would vote for the bill and nine said they would not, mostly along party lines. Two declined to comment altogether.

The legislation, passed in a 241-177 vote, would permanently increase the size of the House to 437 Members. It would grant D.C. a full-voting seat and give Utah an at-large district, as the Beehive State just missed out on getting a fourth Member after the 2000 Census.

Supporters are looking to Sen. Joe Lieberman (ID-Conn.) to take the first step in his chamber. Lieberman, who chairs the Homeland Security and Governmental Affairs Committee, where the bill will be taken up, is a strong ally, as he has worked with D.C. Del. Eleanor Holmes Norton (D) on past voting rights measures.

Lieberman pledged his support for the current legislation before it even passed the House, and he is likely to begin work on it in committee within the next few months, a spokesman said Friday.

“Now that the House has acted, it is time for the Senate to do the same,” Lieberman said in a statement. “I will proudly bring the legislation before my colleagues in the Senate as quickly as possible.”

The measure also has the support of Majority Leader Harry Reid (D-Nev.).

“Sen. Reid supports the bill and looks forward to getting it to the floor as soon as possible,” spokesman Jim Manley said.

Utah Sens. Bob Bennett (R) and Orrin Hatch (R) also are seen as key to passage. Both have said they would support the measure, although Hatch has raised concern about the constitutionality of the at-large Utah seat and the ability to get it through the chamber.

“Some in the Senate have expressed constitutional concerns with other provisions in the D.C. voting rights bill,” Hatch said. “And last year, the president said he hadn’t really looked at the bill. This year, he’s indicated that he would veto it. That makes it very difficult to move this bill forward.”

Davis said Thursday that while Senators such as Hatch do raise legitimate concerns, it is something that can be worked through.

“We have to take care of that behind closed doors,” he said, adding that plans were already under way to get the bill through Congress and signed by Bush.

An unlikely ally in the Senate could be Minority Whip Trent Lott (R-Miss.). Former Rep. Jack Kemp (R-N.Y.), who has long lobbied for the bill, said at a press conference Thursday that Lott has told him privately he would support the measure.

A telephone call to Lott’s office was not returned Friday.

Meanwhile, other Republicans are actively fighting the bill, arguing the Constitution allows only states to be granted Congressional representation. (Proponents argue the Constitution’s District Clause gives Congress control over D.C. representation.)

Senate Minority Leader Mitch McConnell (R-Ky.) has come out against the bill, citing constitutional concerns. A McConnell spokesman said Friday that the Senator would meet with his Conference before making a decision on how to address the bill should it reach the floor, with a filibuster possible.

“Nearly anything controversial in the Senate requires 60 votes,” McConnell spokesman Don Stewart said. “And I don’t know if [the bill] has 60 votes.”

If Roll Call’s admittedly unscientific survey results are extrapolated, 46 Senators would be in favor of the bill with 28 undecided. Meanwhile, in the House 290 votes would be needed to override a veto (if 435 Members vote), but the bill only received 241 votes last week.

Other Republicans are taking action immediately. After the House passed the bill on Thursday, the National Republican Congressional Committee went after Democrats in moderate districts who voted for the bill, even though most of the pre-vote activity took place in D.C. and to a lesser extent Utah.

The NRCC sent press releases to districts represented by 13 Democrats, including Reps. Zack Space (Ohio), Heath Shuler (N.C.) and Tim Mahoney (Fla.).

“Ignoring basic Constitutional facts that are learned by elementary school students across America everyday, Zack Space voted with House Democrats to disregard the Constitutional amendment process and expand voting rights to the District of Columbia,” one release reads. It later continues: “If Zack Space can’t acknowledge the fundamental principles in the U.S. Constitution, it begs the question: Is he fit to hold office?”

Despite the growing opposition, supporters of the bill remained confident last week.

Utah Rep. Chris Cannon (R) said he expected Bush to sign the bill if it passes the Senate, and he predicted the Senate would defer to the House on the bill.

“This is about us and how we govern ourselves,” he added.

Kemp promised to continue to lobby his Republican colleagues in the Senate and predicted an eventual victory.

“If they want to be the party of Abraham Lincoln … they are going to vote for this very important bill,” Kemp said.

Cannon said passing the bill “is the right thing to do,” while D.C. Mayor Adrian Fenty (D) said passage represents “a statement about our country’s principles, values and morals.”

But even if the bill is signed by the president, there likely will be a third mountain to climb: the judicial branch.

“There are those who think it is constitutional, and those who think it is unconstitutional,” Judiciary Chairman John Conyers (D-Mich.) said. “Can’t we let the courts decide?”

Emily Yehle, Daniel Heim, Jamie Weinstein, Marnette Federis and Andrea Kemp contributed to this report.