A group of Senate Republicans this week outlined a counterproposal to President Biden’s $2.3 trillion American Jobs Plan, saying their $568 billion pitch focuses on what they deem “core infrastructure” — transportation networks, water systems and broadband Internet.

“This is the largest infrastructure investment Republicans have come forward with,” Sen. Shelley Moore Capito (R-W.Va.) said Thursday while unveiling the proposal. “This is a robust package.”

Capito, her party’s leader on the Environment and Public Works Committee, said she hoped the proposal would be a starting point for negotiations with the White House.

On transportation funding, the two plans at first glance might not look so far apart, proposing something close to a half-trillion dollars in spending. But there’s a key difference.

Congress typically passes long-term transportation funding bills, currently worth about $300 billion over five years. For example, between 2016 and 2020, Congress provided the $300 billion for roads, transit and rail, with a separate measure funding airports. The Biden plan expects that Congress will continue to provide at least that much money in the coming years. But the Republican proposal includes that $300 billion as part of its total.

Directly comparing each aspect of the plans is tricky, in part because neither is fully fleshed out.

There also are major elements of Biden’s plan that Republicans are not proposing to fund or which don’t neatly compare with existing transportation spending. That includes $100 billion in incentives for people to buy electric vehicles; $20 billion to pay for electric school buses; $25 billion to aid minority communities harmed by past infrastructure spending; and a $25 billion program to fund the largest of transportation projects.

Jeff Davis, a senior fellow at the Eno Center for Transportation — a Washington-based nonprofit that analyzes transportation policy — examined what Biden and Senate Republicans are proposing to spend on roads, transit, rail, airports and safety programs over five years, calculating the numbers at $720 billion and $437 billion, respectively. If Congress simply maintained current funding levels adjusted for inflation, the spending in those buckets would total $375 billion over five years. Here’s how that five-year spending breaks down.

Roads and bridges

Biden plan: $383.5 billion, GOP plan: $299 billion (Current level: $260.5 billion)

Both Biden and Republicans are proposing a boost to highway funding. The president’s plan calls for $115 billion in extra money to help repair 20,000 miles of roads and 10,000 bridges. The Republican plan includes less detail on how money should be spent but mentions directing it to states through existing Transportation Department programs.

Transit

Biden plan: $178.8 billion, GOP plan: $61 billion (Current level: $68.8 billion)

Biden’s plan contemplates a huge expansion of the federal government’s support for transit agencies, aiming to provide more communities with access to buses and local rail service while helping to electrify transit fleets. The Republican plan would effectively cut transit funding slightly, once inflation is taken into account.

Rail

Biden plan: $95.3 billion, GOP plan: $20 billion (Current level: $15.3 billion)

The president’s proposal calls for a major boost in funding for rail, an amount that Amtrak says would allow it to expand service to many cities, and which the administration says could help the development of high-speed rail. The Republican plan calls for a modest bump in funds.

Airports

Biden plan: $39.7 billion, GOP plan: $44 billion (Current level: $19.7 billion)

Airports are the one area where Republicans have proposed more funding than the Biden administration, but the plan they outlined this week doesn’t set out how the money should be used. Biden is proposing to fix existing airport facilities and to back programs that would make it easier to get to airports without driving.

Safety

Biden plan: $22.8 billion, GOP plan: $13 billion (Current level: $10.8 billion)

Biden is seeking more money for safety agencies such as federal auto and trucking regulators. The administration is aiming to make roads safer, especially for pedestrians and cyclists. The GOP plan provides slightly more money for safety.