From the latest Gallup poll:

The final USA Today/Gallup measure of Americans' voting intentions for Congress shows Republicans continuing to hold a substantial lead over Democrats among likely voters, a lead large enough to suggest that regardless of turnout, the Republicans will win more than the 40 seats needed to give them the majority in the U.S. House.

The results are from Gallup's Oct. 28-31 survey of 1,539 likely voters. It finds 52% to 55% of likely voters preferring the Republican candidate and 40% to 42% for the Democratic candidate on the national generic ballot -- depending on turnout assumptions. Gallup's analysis of several indicators of voter turnout from the weekend poll suggests turnout will be slightly higher than in recent years, at 45%. This would give the Republicans a 55% to 40% lead on the generic ballot, with 5% undecided.

Republicans Appear Poised to Win Big on Tuesday