After a pair of dramatic votes in the House left President Obama's trade agenda dangling by a thread on Friday, most of the attention turned to Democrats: They had bucked their president in big numbers, despite a last-minute, in-person appeal.

That's true. It is also not very surprising, in the context of recent history. The bigger historical surprise was how many Republicans opposed a landmark bill on free trade.

About three-quarters of the House GOP sided with Obama on so-called "fast track" trade promotion authority. You have to go back to a pair of votes under Bill Clinton -- NAFTA in 1993 and a failed fast-track push in 1998 -- to find the last time such a small share of Republicans supported a major trade bill.

Two-fifths of House Democrats backed Clinton on NAFTA. That's the high-water mark for the party's support for major trade deals in the House in the last two decades. When only 15 percent of House Dems backed Obama on Friday, they weren't on the low or high end of that historical spectrum. They were about in the middle:

Obama effectively needed the House to approve two things Friday: a provision to spend money helping some workers after their jobs were hurt by freer trade, and so-called "fast-track" trade authority that would allow the president to send trade deals to Congress for an up-or-down vote.

The first vote failed overwhelmingly -- only a third of Republicans and a fifth of Democrats supported it. The broader measure squeaked by, though.

There's a lot of attention, and rightly so, on how few Democrats Obama brought along for either vote. (Especially when you compare him to Clinton in 1993.) It's also fair to note, though, that House Democrats have shown little appetite for trade bills since NAFTA. About a third of them voted for the Panama and Korea agreements in 2011. But fewer than 1 in 10 of them backed the Central American Free Trade Agreement under President Bush in 2004, and a slightly smaller share of them voted to give trade promotion authority to Bush than they just did to Obama.

House Republicans, on the other hand, had hovered at or above 90 percent of support for major trade bills since 1998, including previous bills under Obama. But some conservative activists have opposed this trade push, on a variety of grounds, contributing to the GOP defections this time.

For Obama's trade agenda to progress, he needs the worker-reimbursement provision - something conservatives have tended to oppose, historically - to pass on a re-vote, likely next week. That vote is now the proxy vote for "should the trade agenda move ahead under Obama?"

The president would certainly like more Democrats to join his cause for it. But to win, he probably needs a lot more support from Republicans. NAFTA numbers would suffice.