Here’s the latest from Gallup:

Gallup Daily tracking for the week ending April 11 puts Republicans slightly ahead of Democrats, 48% to 44%, in the congressional voting preferences of registered voters nationally. This marks the third week since the U.S. House passed healthcare reform on March 21 that the Republicans have tied or led the Democrats.

And this:

Gallup will not begin identifying likely voters for the 2010 midterms until later in the year. However, at this early stage, Republicans show much greater enthusiasm than Democrats about voting in the elections. Enthusiasm among members of both parties peaked shortly after passage of the healthcare reform bill on March 21, but has since tapered off slightly.

Forty-eight percent of Republicans are “very enthusiastic” about voting in this year’s congressional elections; the figure for Democrats is 30 percent.

This data isn’t particularly surprising any more, which is why it should be so alarming to Democrats.