WASHINGTON - A big Republican win in Tuesday's United States congressional elections could jolt US relations with Europe by affecting issues such as arms control, climate change and relations with Turkey.

Foreign policy has not been a factor in the campaign, which has been dominated by economic and other domestic issues. But if Republicans, as expected, win control of the House of Representatives and make gains in the Senate, the impact will be felt beyond US borders.

Though Congress does not run US foreign policy, it can influence it in many ways, and President Barack Obama could find many of his priorities stalled or tripped up by lawmakers.