The Economonitor has been trying to avoid the midterm elections as much as possible: This is an economics blog, not a politics blog. As this blog is being written, TradeSports has the Republicans keeping the Senate (67.5% probability) but losing the House (17.8% probability of retaining control there).

But since it's such a politically-fraught day, I'll concede one post to political matters, and give the floor to Greg Mankiw, who reckons the Republicans are much better than the Democrats on free trade:

The 1993 roll call vote in the House found 132 Republicans in favor of NAFTA, 43 against. Among House Democrats, there were 102 in favor, 156 against.
In the Senate, the same story. Among Republican senators, there were 34 in favor of NAFTA, 10 against. Among Democratic senators, 27 were in favor, 28 against.
Since NAFTA, the difference between the two parties has, if anything, grown larger. When the Central America Free Trade Agreement came up for a vote in 2005, the House produced 202 Republicans in favor, 27 against. The Democrats had only 15 in favor, 187 against.

Of course, Mankiw's commenters (who seem to be a pretty Dem-leaning bunch) aren't taking this lying down. Some concede his point, but others contest it. Mark Witte:

Clinton worked hard to put together a coalition to pass NAFTA (which to give credit where due, was largely negoitated by the GHWB administration). As such, he expended political capital to get enough members of his party to pass this.
How does this compare with Reagan's caving in to the auto industry, or GWB's caving in to agriculture, steel, and textiles? Bush has had a much stronger legistlative position than Clinton ever had, and what has he done with it for trade?

And twicebitten:

Clinton was also much more successful at culminating the Uruguay round that coincided with his Presidency (which included important agreements and led to the creation of the WTO). Under Bush and with Republican leadership of both houses of Congress the Republicans have absolutely squandered the Doha round.

The difference seems to me to be that Mankiw's talking about the legislature and not the executive. The Bush White House has achieved very little on the free-trade front, in contrast to the Clinton White House. But if you put it to a vote, Republican legislators are more likely to support free-trade initiatives than Democratic ones.

Doha Trade Talks Suspended: What Next?