After two and a half months of open hostility from his own Conference, numerous false starts, a short-term extension and a host of revisions and rewrites, Speaker John Boehner on Tuesday appeared close to passing some sort of highway extension legislation.

The House is scheduled today to take up a modified version of the Ohio Republican’s most recent plan — a 90-day extension of transportation programs that could include some reforms sought by conservatives as well as Keystone XL pipeline language, all of which are designed to give House Republicans leverage in conference negotiations with the Senate.

The legislation drew an immediate rebuke from the White House.

“Because this bill circumvents a long-standing and proven process for determining whether cross-border pipelines are in the national interest by mandating the permitting of the Keystone XL pipeline before a new route has been submitted and assessed, the President’s senior advisors would recommend that he veto this legislation,” the Office of Management and Budget announced in a Statement of Administration Policy on Tuesday.

While a veto threat might cause problems during the conference with the Senate, Boehner has had more pressing concerns, namely finding enough Republicans to even pass a bill in the House — which leadership aides hoped the current strategy would resolve.

Boehner came into the week intent on moving a “clean” 90-day extension of transportation programs along with language on the Keystone XL pipeline as a vehicle to begin conference proceedings with the Senate, which passed a bipartisan bill of its own last month with 74 votes.

Boehner had thought such a version had the best chance of passing the House on a party-line vote, since conservatives had bashed his previous plans, including a sweeping reform of highway and transit programs that also tied revenues from oil and gas exploration to funding for highways.

Late last week, Boehner tasked Majority Whip Kevin McCarthy with selling the bill to his Conference. The California Republican convened a Friday conference call on the bill and reached out to individuals in the GOP Conference.

But with conservatives demanding reforms be included — and threatening to once again blockade Boehner’s efforts on the transportation front — he agreed to allow a handful of amendments making key reforms to the program, most of which are expected to be passed during consideration of the bill today.

Although vote tallies are still unclear, leadership aides said they now have hope those amendments and the package of reforms will provide McCarthy with enough influence to score a majority vote.

But the plan doesn’t come risk-free. “It’s a dangerous strategy,” one veteran GOP aide said, explaining that while allowing a handful of amendments could, in theory, help round up enough votes to get the bill to conference, it could also end up angering Members who had wanted their own crack at modifying the bill.

Even if hurt feelings don’t derail the legislation, they could factor into any eventual vote on a conference report because those Members left out in the cold will be precluded from offering changes to a conference report.

Of course, that assumes House GOP negotiators are able to extract enough political concessions from the Senate to make a push for final passage worthwhile. Given the history of the legislation this year, that could be a tall order.

Democrats were clearly pleased with Boehner’s woes.

Minority Whip Steny Hoyer on Tuesday repeatedly hammered Republicans over their inability to marshal their troops to pass a highway bill. “Frankly, the Republicans rejected a chance to pass … a bill that three-quarters of the Senate is for,” the Maryland Democrat said, noting that despite their opposition to the Senate bill, “they can’t even get to a significant number [of Republicans] — where a few of us voting for it would make the difference.”

Boehner has been forced into “trying to cobble together some modicum of a bill that they can get through the House of Representatives. … I just think it’s unfortunate that the Republican Party can’t come to reasonable compromises,” Hoyer said.

The administration also got into the act, arguing in its SAP that “this legislation would miss a critical opportunity to provide more certainty to States and localities as they undertake the long-term planning and execution of projects and programs that are essential to creating and keeping American workers in good paying jobs.”

Still, it was unclear whether Hoyer would end up whipping against the bill or allow it to pass uncontested to begin conference talks. “We need to get a bill done. We need to give stability” to states and contractors, Hoyer said. “We’re hopeful we can get to a conference … but I’m not saying I’m for their plan,” he added.