By John D. McKinnon 

WASHINGTON--Fresh off their victory on trade legislation, President Barack Obama and the Republican Congress in the coming weeks will face another test of their ability to work together on an issue important to business: highway funding.

Early indications are that the fight will prove at least as difficult as just-completed trade legislation tussle, where Republicans joined forces with Mr. Obama to overcome Democrats' objections.

This time, the debate is complicated by the issue of taxes, as some House Republicans led by Ways and Means Chairman Paul Ryan (R., Wis.) are weighing the possibility of teaming up with Mr. Obama and Senate Democrats, including Charles Schumer of New York, to use corporate tax changes to help pay for an infrastructure package.

Messrs. Ryan and Schumer are expected this week to step up their efforts to build bipartisan support for a deal combining a tax overhaul with highway funding. But the idea faces significant hurdles.

Other Republicans, particularly in the Senate, are cautious about the plan, say aides and others familiar with their thinking. In particular, they are concerned that a tax overhaul benefiting big U.S. multinational corporations might open some of their vulnerable incumbents to populist attack by Democratic opponents next year.

"The politics are difficult. It'll be hard for some members to explain why they are doing tax legislation benefiting multinational businesses and not local businesses and local individuals," said Jon Traub, a former GOP congressional aide who's now at Deloitte Tax LLP. However, he thinks there is a strong chance lawmakers will attempt such legislation because the alternatives are even more difficult.

Even big businesses are divided over the idea, with many concerned it could sap momentum for an eventual broader tax overhaul.

"I think [a tax overhaul] for roads is a lot harder than it looks," former Ways and Means Chairman Dave Camp, a Michigan Republican who now works for accounting firm PwC, said on Thursday.

Among ideas being floated is a partial tax overhaul that would change U.S. rules that discourage American multinationals from bringing home foreign profits and paying U.S. taxes on them.

By now, some $2 trillion in such "stranded" profits has built up offshore. An influx of these foreign profits could generate significant new tax revenues for the U.S., a share of which could be earmarked for the troubled Highway Trust Fund.

The highway program faces both short-term and long-term problems. In the short run, the trust fund's authorization runs out at the end of July. Over the long term, its finances have suffered because the federal gasoline tax of 18.3 cents per gallon has been hurt by higher-mileage vehicles, reduced driving and inflation.

The trust fund, absent reauthorization, is projected to dry up in coming weeks, slowing construction projects nationwide.

For Republicans, though, the highway-funding debate generally raises painful questions. Approving any type of new taxes for a highway bill is increasingly difficult.

Historically, debates about transportation and infrastructure bills have broken down along geographical lines, not partisan ones, said former Sen. Evan Bayh, an Indiana Democrat. But in the current political environment, "there will be an element within the Republican caucus that won't be in favor of raising revenue from any source," he said.

The debate also opens the door to increased spending levels for the fund in coming years, another potential problem for some GOP lawmakers.

For Democrats, the highway debate generally represents a welcome change from the fractious politics of trade, where many were forced to oppose their own president.

Funding roadways is a cause that unites Democrats--as well as most Republicans--because of the jobs and other benefits it creates.

Still, the highway debate is raising the possibility of unlikely alliances. Mr. Ryan has spoken with Sen. Schumer recently about the possibility of joining forces on a highway deal, according to a person familiar with the matter. Sen. Schumer has been working for a while on an overhaul of international tax rules that could help cover highway needs.

Ways and Means aides said on a blog post last week that "if we find common ground on limited changes to our tax system, we'll explore what can get done over the next year and a half. It could even provide the solution to fund a multiyear highway bill."

In a statement on Thursday, Mr. Schumer expressed optimism.

"International tax reform could put gas in the tank when it comes to getting a long term highway bill, which we desperately need this year," he said. "It's a complicated needle to thread so it may take some time, but I'm hopeful we can get a bipartisan deal in the next several months."

Senate Republicans, however, are more skeptical.

Finance Chairman Orrin Hatch (R., Utah) also questions whether it is politically feasible to link highway funding to international tax changes.

At a recent hearing, Mr. Hatch noted that one version of the idea advanced by some Democrats--cutting tax rates on foreign income to encourage companies to bring home more money voluntarily--actually would cost the government money. "In other words, it is not a serious proposal to pay for a long-term highway bill," Mr. Hatch said.

The Business Roundtable, a group of CEO's of major firms, issued a statement recently raising concern about the concept. Using repatriation revenue to support "stand-alone unrelated new spending would imperil the ability to achieve meaningful tax reform," said Mark Weinberger, who is CEO of accounting firm Ernst and Young and chairman of the Roundtable's tax policy committee.

If the effort to use a tax overhaul to pay for road work fails, lawmakers likely will fall back on a patchwork approach to fund the program for the next six months to two years. That could include a mix of narrow spending cuts and revenue increases, possibly including tougher enforcement of existing taxes or expanded oil and gas exploration.

Lawmakers also might choose simply not to offset the cost of some or all the highway spending, as they have in the recent past.

"Obviously there's an appetite in Congress to do things that are fiscally irresponsible," said former GOP Sen. Judd Gregg of New Hampshire, a onetime Budget Committee chairman. "It's not a way to govern, but I lost this fight so often [on highway funding].... I just got run over, every time."

Write to John D. McKinnon at john.mckinnon@wsj.com