WASHINGTON - Angry conservatives are driving the approval ratings of President Bush and the GOP-led Congress to dismal new lows, according to an AP-Ipsos poll that underscores why Republicans fear an Election Day massacre. Six months out, the intensity of opposition to Bush and Congress has risen sharply, along with the percentage of Americans who believe the nation is on the wrong track. The AP-Ipsos poll also suggests that Democratic voters are far more motivated than Republicans. Elections in the middle of a president’s term traditionally favor the party whose core supporters are the most energized.