Following the President's Monday night speech, Democrats enjoy a 15-point advantage on the Generic Congressional Ballot. A Rasmussen Reports national opinion survey of 1,000 Likely Voters found that 48% would vote for the Democrat in their district if the election were held today. Just 33% would vote for the Republican.

Just 58% of conservatives say they would vote for the Republican candidate.

Two weeks ago, the Democrats had a ten-point advantage, 46% to 36%.

While the Democrats gained ground over the past two weeks, underlying views about immigration have changed little from earlier surveys.

By way of comparison, the May 1 immigrants-rights rallies had no impact on the Generic Congressional Ballot or public opinion on the immigration issue.

Forty-two percent (42%) of voters trust Democrats more on the immigration while 37% have more faith in Republicans. Among those who say the issue is very important, Republicans are preferred by a narrow 43% to 39% margin.

Another recent survey found Democrats with a 12 percentage point lead on a generic 2008 Presidential ballot. However, a third party immigration enforcement candidate could shake up the race.